Driving in the United States

The United States of America is the birthplace of consumer car culture, and driving is often the best way to savor the sights of this vast country. The country's great network of roads provide optimum access to the colorful natural wonders that are in between and sometimes far from the multicultural population centers. Most of the sights you typically see on a USA postcard are either best or only accessible by car. Driving long distances in the USA, a road trip, is a quintessentially American form of travel.

Understand


While Karl Benz may have invented the first automobile in Germany, car ownership only became an affordable option for the general public in 1908, when Henry Ford implemented the assembly line and was able to begin mass producing his signature Model T. While Ford was neither the first nor the only one to mass-produce cars, he was the most influential one and the Model T sold in the millions in a market still dominated by producers with yearly sales figures in the hundreds or thousands of cars. Thus, America's love affair with the automobile — itself a concept introduced to the public consciousness through marketing — was born. American consumer car culture truly took off in the 1950s, in a global market dominated by American car manufacturers such as Ford, General Motors and Chrysler. Public transportation networks in many American cities declined or were dismantled as the popularity of private car ownership exploded. In fact, many streetcar companies were bought by GM, the streetcar tracks were slashed, and the routes were later replaced by GM buses before being discontinued altogether.

Today, the vast majority of adult Americans own cars, and driving is usually the most popular way of getting around the country, as well as in or between cities. Compared to European and East Asian cities of similar population sizes, public transportation in American cities tends to be unreliable and infrequent, so renting or bringing your own car is usually a very good idea. This is true even of many of the very large cities, including Los Angeles, Atlanta, Miami and Detroit, even though public transportation has made some inroads there in the 21st century.

Driving conditions vary between the different regions, states, and areas within states. If you are more into scenery, the West Coast, Rocky Mountains and Southwest offer a better experience, at the cost of speed because of hilly terrain, and of course, breathtaking views that entice you to stop. If you are more inclined to culture than virgin forests and snow-capped peaks, you may want to travel in states with greater population density on the three coasts (East, West and Gulf) and the Great Lakes states. Major roads are generally well paved and thoroughly maintained. However, there are areas, especially outside the Interstates, where cellphone coverage is spotty or nonexistent and it will take you many miles to find gasoline and refreshments. It is highly advisable to plan ahead if you are travelling long distances in remote areas by checking the weather, and have a GPS ready to find the route and the nearest resting area, but keep in mind that GPS systems do not work if there is no signal. If you are traveling through areas with no signal for dozens of miles, such as on the Central Coast of California, paper maps or printouts of routes and directions are highly advisable. Do your best to make sure you have enough power on a cellphone to call the emergency number, 9-1-1 in case of emergency, where signal reception may be unavailable. Satellite phones are not common but may be necessary if you often roam off-the-beaten-path destinations.

With the exception of military and scientific usage, the United States does not use the metric system, instead retaining its own customary units. This means that road distances are indicated in miles, and speed limits are indicated in miles per hour (mph). 1 mile is equal to 1.609 km. Canada and Mexico use the metric system; automobile speedometers (but not odometers) normally display both units. Vehicles whose speedometers display only one set of units at a time usually have an electronic switch allowing the driver to toggle between US and metric units on demand; check the owner's manual to find out how to switch units.

Fuel (which Americans refer to as "gas" or "gasoline", not "petrol") is dispensed in US gallons. A US gallon (3.78 liters) is 0.84 imperial gallons (quarts, pints and fluid ounces all also differ between U.S. and imperial measure). US fuel prices tend to be lower than those in Canada or Europe due to differing levels of taxation; there is also variation between the different states for the same reason.

Also notable is the way Americans measure fuel efficiency. Unlike most of Europe it is not measured by how much gas a car needs to cover a given distance (e.g. liters per 100 km) but rather how far you can drive on a gallon, thus miles per gallon (mpg). This makes comparisons of European and American fuel efficiency difficult, but keep in mind that a higher number is better (e.g. 50 miles per gallon is better than 10).

Unique to the U.S.


Some features of driving in the U.S. differ notably from the rest of the world:


 * Highway signage is always in miles, including fractions. To add to the confusion, car navigation software like Android Auto may use feet or decimal miles.  Learn metric equivalents for common measurements: 1/2 mi is ~800m, 1/4 mi is ~400m, 1000 ft is ~300 m, 0.1 mi is under 200m.  Switching your navigation to metric may also help.
 * Instead of yielding rules or roundabouts, smaller road junctions are often signposted as all-way stops (aka 4-way stops, 3-way stops). This means every car coming to the junction must fully stop at the sign, then proceed through the intersection in the order that they arrived.  This works better than you'd think, but if there's any doubt who's first, make eye contact with the other driver(s) and signal who can go first.  If turning, right turns go first.
 * Right turn on red, meaning turning right at a red traffic light (after a full stop and if there's no traffic), is allowed and expected throughout the U.S. unless signposted otherwise, except in New York City.
 * Rear turn lights are often red, instead of orange/amber; don't confuse them with brake lights at night.
 * In urban and suburban areas, it is common for freeways to have very closely spaced exits, it's not unusual to have two or even three within a mile. Pay careful attention to exit numbers, and beware the rightmost lane on a busy freeway: it often turns into an EXIT ONLY lane, sprinkled with THRU TRAFFIC MERGE LEFT warnings.

Border crossings
Crossing the border with Canada in a rental car is relatively straightforward in both directions with the large multinational car rental companies, but you need to let them know in advance that you wish to cross the border, even if you don't plan to stay overnight, as additional documentation will be required. Most of these companies will allow you pick up a car in the U.S. and drop it off in Canada and vice versa.

Crossing the border with Mexico is much more complicated. Mexican rental cars are typically not allowed to be driven into the U.S. To drive a U.S. rental car into Mexico, you will need to purchase additional Mexican insurance, and usually cannot drop the car off in Mexico. In addition, you will usually not be allowed to drive beyond the border region

Traffic laws
Driving laws are regulated by the respective state governments, and road rules may vary slightly from state to state. Nevertheless, there is in general a consistent system of road signage throughout the United States, and differences in road rules between states are, for the most part, fairly minor.

All states publish an official driver's handbook which summarizes state driving laws in plain English, with some states providing a Spanish version as well. These handbooks are usually available both on the Web and at many government offices. AAA publishes a AAA/CAA Digest of Motor Laws (now available online for free) that covers especially a few difference of traffic rules applied by all U.S. states and Canadian provinces.

General driving laws
With the exception of the U.S. Virgin Islands, Americans drive on the right in left-hand drive vehicles and pass on the left, as in Canada and Mexico. White lines separate traffic moving in the same direction and yellow lines separate opposing traffic. Red lights and stop signs are always enforced at all hours in nearly all U.S. jurisdictions. At all intersections, vehicles must stop behind the thick, white line painted across the road and cannot block crosswalks. Turning right at a red light (after coming to a complete stop and yielding to cross traffic) is legal in every state, though exceptions exist (such as throughout New York City and where signage or signals explicitly prohibit it). In most states, you may turn left at a red light from a one-way street to another one-way street unless explicitly prohibited by signage. This particular point is specifically an issue in the Kansas City area—Missouri bans such turns statewide, while Kansas allows them. Road rules differ slightly from state to state, though they are for the most part uniform.

Making a call or a text message while driving is very dangerous and violators face a hefty fine if caught. The use of horns is also regulated: They may be used only in case of giving warning to other drivers.

Drunk driving is strictly forbidden and subject to fine, arrest and/or suspension of one's driver's license, and if you are convicted of felony drunk driving, you are likely to also be banned from reentry to the United States if you are not a citizen or permanent resident. The general limit that qualifies for drunk driving is if the blood alcohol content is .08, which means 8 grams of alcohol per 10 liters of blood, but even an amount lower than that can still get you in trouble if you are driving erratically and the police consider you impaired. Utah has an even lower threshold for drunk driving at .05. Police do random breath tests in most states and a test is always conducted in the event of an accident. When you are pulled over for erratic driving, especially at night, police will almost always assume that you are drunk driving unless you explicitly deny the claim by citing other factors and/or pass the breath test. Drinking and driving is never a good idea - even if your alcohol level may have fallen below the legal limit - and if you are planning to drink, do appoint someone in advance to be your "designated driver" or arrange for transportation by taxi or public transit. It should go without saying, but if you intend to drive, stay away from all alcohol for that evening.

Having an open container of alcohol anywhere in a car other than in the trunk is also forbidden in most states; this can be heavily fined.

Licenses
Licenses are issued by the governments of the respective states and territories; licensing laws vary from state to state. Most visitors aged 18 or over are allowed to drive on their foreign license when visiting on short trips, if it is written in English. Licenses not written in English generally have to be accompanied by an International Driving Permit (IDP) or a certified translation before you are allowed to drive.

For longer stays (above a year), you may be required to convert your foreign license to a local one in the state you are residing in. The requirements vary from state to state, but most foreign license holders would be required to sit for theory and practical tests before their licenses can be converted, but they are sometimes waived for holders of some Canadian and European licenses. The list of countries whose license holders are exempt from testing requirements varies from state to state.

Speed limits


Speed limits are usually about on most city roads, although in New York City the speed limit on most roads is. Speed limits on limited-access highways usually range from. Many interstate highways mandate a minimum speed of.

Speed limits on the interstate highways can vary from state to state, and also according to geography (for example, slower on mountain passes and within cities than on long straight rural sections). Posted speed limits on through roads can range from as low as in densely urban areas to as much as  in rural stretches of Texas, but mostly they'll be between. The speed limits (in miles per hour) are always clearly posted on interstates.

Most American drivers tend to drive calmly and safely in the sprawling residential suburban neighborhoods where the majority of Americans live. However, downtown surface streets and freeways around the central areas of big cities often become crowded with a significant proportion of "hurried" drivers, who exceed speed limits, make unsafe lane changes, or follow other cars at unsafe close distances (known as "tailgating"). Regard for and enforcement of posted speed limits is somewhat unpredictable and varies widely from state to state. Not exceeding the pace of other drivers will usually avoid a troublesome citation. Beware of small towns along otherwise high-speed rural roads (and medium-speed suburban roads); the reduced speed limits found while going through such towns are strictly enforced as they represent a lucrative source of revenue. They are referred to as "speed traps"; a common tactic is for officers to lurk at the town line where the posted limit drops abruptly and issue many tickets.

American drivers often drive 5 – over the posted speed limit; driving slower than the speed limit can actually be dangerous. A good rule of thumb is to avoid driving much faster than 5 mph over the speed limit, and be sure that some other cars are always passing (overtaking) you; avoid being the fastest or the slowest vehicle. Slower traffic is required to keep to the right while faster traffic passes on the left, though in many areas this is rarely adhered to.

Lane markings
Lines dividing lanes of traffic moving in the same direction are painted in white, while those dividing traffic moving in opposite directions are painted in yellow.

On rural undivided highways, the center dividing line indicates whether or not passing is legal. A broken dividing line indicates that you may move to the other side of the road to pass if it is clear. A solid dividing line indicates that no passing is allowed and you may only move over to the other side to avoid an obstruction. A broken line next to a solid line means that you may move to the other side of the road to pass if you are driving on the side of the broken line but not if you're driving on the side of the solid line.

School buses and emergency vehicles


School buses, painted a distinct shade of yellow and clearly labeled as such, are a common sight on American roads. They may be any size; sometimes they may even be regular vehicles with yellow signs and lights. They will be most common near schools and on local roads in the early morning and midafternoon, when students come and go to school. School buses you see at other times of the day are likely to be taking students on trips or to or from athletic contests, or empty and being taken to the garage.

During morning and afternoon hours, when they are picking up students or taking them home, they will be traveling slowly and making frequent stops at driveways or side streets, sometimes with shelters, usually with some parents present especially for younger children. As such traffic often backs up behind them. Try not to get too frustrated—their drivers are aware of this, and sometimes they will at intervals pull over and let traffic pass.

Drivers visiting from other countries should take heed of special laws that apply to school buses. Most importantly, when a school bus stops on a road to discharge or pick up students, it puts on flashing yellow lights and then flashing red lights. When the latter are on, usually while its passengers are going to or from the bus, all traffic in both directions must stop and cannot pass the bus, regardless of whether the passengers (usually children) need to cross the road, until the yellow lights resume. Many states require stopping even if the road is divided, but this rule is not universal—some states that allow traffic to continue in this situation post signs to remind drivers not to stop if a school bus is on the opposite side of a divided road (for example, Kentucky sometimes but not always does this). In California and some other states, when a school bus stops at an intersection, traffic in all directions must stop.

This is not just a law, with stiff fines for even the first violation—it has come to assume the status of a social norm. As such, even an inadvertent violation of this law at a slow speed will likely earn you some angry words from the bus's safety monitor (if there is one) or, worse, a confrontation with an angry parent or parents, even if there are no police officers present (and in some states, the bus driver's word can support a ticket; increasingly, as well, some school districts are equipping their buses with cameras).

Also be aware of state laws regarding traffic on the opposite side of a divided highway from a school bus—if you're in a state that allows such traffic to proceed, stopping for a school bus on the other side of the median (or, in some states, the other side of a dedicated left-turn lane) can get you a ticket. For example, Indiana, Kentucky, and West Virginia, which are successive states along Interstate 64, differ on whether a driver must stop for a school bus on a four-lane (or greater) road while going in the opposite direction. West Virginia requires stopping on all non-Interstate highways, regardless of the number of lanes or the width of the median. Indiana requires stopping unless the road has a physical divider or an unimproved median. Kentucky allows such traffic to proceed even if the only separation is a double yellow line. Nonetheless, even if you know for a fact you can proceed in such a situation, take care!

While it is easy to tell when you must stop if you are behind a school bus, you should stay alert during the appropriate times of day for buses going the opposite direction, as there is no room for error. To help drivers, special neon-colored warning signs depicting a school bus stop are being installed at curves near locations school buses frequently stop at.

Another law requires that school buses come to a stop before going over any grade (level) crossing with active railroad tracks, regardless of whether there is a train coming. So, if you find yourself behind a school bus, be prepared for this. In some states, school buses are required to stop at such locations even if they aren't carrying children.

Like their counterparts in many other countries, American drivers are required to pull over and make way, if necessary, for any police cars, fire trucks and ambulances responding to emergencies (i.e. with lights flashing and/or sirens sounding). Also included in this law, in some states, are the personal vehicles of volunteer firefighters or ambulance personnel, which can be distinguished in most states by a red, blue or green flashing light in the windshield or on the roof. This, too, has come to be treated as a social norm, so drivers often pull over well before necessary, or even when it is not necessary. If you violate it, as with the law on stopped school buses, expect some measure of disapproval—and little flexibility with the stiff fine if you receive a traffic ticket for it. You aren't legally required to pull over if the emergency vehicle is traveling the other direction on a divided highway where there is a physical barrier between traffic directions, but many people do so anyway.

Dealing with the police


Unlike other countries, in the United States there are many separate law enforcement agencies, and this is very apparent in how traffic-law enforcement is handled. State, county, tribal, and local police agencies can all be seen patrolling the roads, but not all of them may be allowed to pull drivers over depending on the situation (in many states, for instance, only the state police or highway patrol will be seen on interstate highways). This may also affect how any traffic stop you are involved in is ultimately resolved.

Whatever their jurisdiction, police officers who wish to pull you over for a traffic violation will let you know by pulling their vehicle up behind yours, usually very quickly, and turning on their flashing lights. You do not have to stop immediately—but don't take too much time; try to find an area ahead with enough space so that you and the officer can safely pull far enough off the road for him or her to walk up to your window without worrying about the passing traffic (And note that if you see a police vehicle ahead with a stopped motorist "feeding the bear", many states have "move-over" laws requiring approaching traffic to either slow down considerably as it passes the stopped police car or pass in the opposite lane, even on a two-lane road, where that is practical). A disused parking lot is ideal for this; as long as it is lit at nighttime and visible. The police officer will appreciate this.

Some visitors from other countries may find the appearance and demeanor of American police officers intimidating, perhaps influenced by media coverage of incidents at traffic stops between police and members of ethnic minority groups, or just because of how police officers are depicted in American movies and television. There is some truth to this; more American police officers are killed in traffic stops than in anything else they do on the job, so departments frequently show their officers dashcam videos of such incidents as part of their ongoing training, and these are often at the back of those officers' minds when they pull you over. For the same reason, you may notice that the officer has his or her hand on their gun as they approach your vehicle—don't take this personally; again they are usually following department policy requiring this.

You can help ease these fears as he or she approaches by keeping your hands on the top of the steering wheel the way you were taught to hold it when you learned to drive, so the officer can see them. If it is dark out, turn on the interior light. If it is bright and you are wearing sunglasses, take them off so the officer can look you in the eyes (even though he or she may not do so themselves). It's also usually a good idea to put out any cigarette you may have been smoking. Mute the car audio or turn it off as well. Turn the engine off. Open the window as much as possible given the weather conditions.

The officer will likely not approach your car at first; they will be in the car letting their dispatcher know they've initiated a traffic stop and having a check done on the vehicle's license plate to find out who the owner is and make sure it is not one reported stolen. Keep your hands visible and remain in your vehicle. Never exit your vehicle unless specifically instructed to do so. This can result in your injury or detention for fleeing arrest, even if that is not your intention.

When they do walk up to your window, greet them with a simple "hello, officer" and nothing else. Do not try to argue at any time that you weren't speeding, or ask "What's the problem?" (admit it, you already know). They will ask for your license and registration (and, in some states, proof of insurance or other financial responsibility). If you are driving a rental car, the rental agreement will suffice for the latter two. These documents will probably be in several locations within the passenger compartment; as you reach into your pocket or open the glove compartment to get them, tell the officer what you are doing - and wait for a response - so he or she won't think you're getting a gun. In some cases, it may be more practicable to tell the officer where something is and ask them whether they can reach for it themselves but use your own best judgment.

The officer may then either tell you what you are being pulled over for or ask if you have an idea. While this latter course of action is a violation of your constitutional right against self-incrimination, it's usually better to just answer the question as truthfully as you can since he or she may be more inclined to give you any break in his or her power to give if he or she feels you understood what you did wrong, rather than take a stand for the Fifth Amendment. After that, if he or she is inclined to just let you off with the warning, they will do so and let you go. If not, they will return to their car and write you a ticket (often printed from the computer in their car, to make it easier to read).

Again, stay in your vehicle unless the officer requests that you get out, which they have the right to do for their own safety (so you should comply unless you have some medical reason not to). When they give you the ticket, they will tell you what court to send the ticket to with your plea, and tell you any breaks they may have given you such as not writing a ticket for that burnt-out tail light. And then you will be free to go unless some other issue has arisen.

Do not attempt to bribe an officer, as it is a felony punishable by a hefty fine and possibly a prison sentence. Almost no officers will accept bribes, and you will instead be arrested.

The U.S. Constitution's restrictions on searches are less stringently applied to vehicles than structures. During that walk up to your window, the officer will have been able to look in your windows. If they see anything that's illegal to have (such as open containers of an alcoholic beverage, in every state but Missouri, or drug paraphernalia), they can arrest you on that charge and will have probable cause for a search of the vehicle without a warrant since "the eye cannot commit a trespass". If they see anything that might also indicate that you're breaking the law, that is considered reasonable suspicion and can also be grounds for a more limited search of the car (for instance, empty bottles of alcohol). If they suspect you are transporting drugs in the vehicle, they have the right to have a dog walk around the car and sniff the air next to it. You will not be free to go until the search is completed, or they tell you that you are.

When they do give you the ticket, thank them—and don't say anything else. If you truly believe you were wrongly cited, it's better to hire a traffic lawyer if you can and contest the charge in court than argue with the officer. You can either plead guilty and pay the fine (in person, online, or through the mail), or plead not guilty and show up in court on the appointed day, where it is likely that you will be offered a deal where you are charged with something less severe. Be aware that fighting simple offenses in court can lead to higher costs if found guilty.

Road networks


Roads in the U.S. are generally well maintained. The U.S. is crisscrossed by a large network of controlled-access highways known as interstates, meaning that travelling between nearby cities is usually a breeze. As most Americans drive to get around their respective cities, most major cities are also covered by a dense network of elevated highways.

There are no regular ferries between the U.S. mainland and Hawaii, meaning that the only way to bring your car over is to ship it on a freighter, which can work out to be rather expensive. The only way to travel overland between the contiguous 48 states and Alaska is to drive through Canada. Owing to the low population density, the interstate highways in Alaska are not built to freeway standards, and for the most part are simply two-lane undivided highways. Some cities in Alaska, such as the capital, Juneau, are not accessible by road at all, though there is a ferry network that allows cars to be shipped to some of these road-inaccessible coastal cities.

As with major cities around the world, congestion can be expected during the morning and evening peak hours in American cities. Nevertheless, due to the unreliability of public transport in most American cities with some notable exceptions on the East Coast, West Coast, and Great Lakes states, driving is still the most convenient way of getting around.




 * Interstate Highways are fast and long distance routes that connect major cities, which usually have between two and five lanes in each direction (typically two outside major cities). Most are frequented by semi-trucks. The speed limit usually varies between 60mph in cities to 85mph in parts of Texas, and there can be lane restrictions such as for High Occupancy Vehicles (vehicles with two or more occupants) symbolized by a white diamond (◊). While there are no commercial rest areas directly adjacent to the Interstate, there are usually road signs that tell restaurant, lodging, and refuel options at a nearby exit, or you can get to truck stop, an establishment that caters to long-haul truckers but is open to all travelers; truck stops provide several services all in one building, with a "greasy-spoon"-style restaurant, gas station, general store, and even hot showers. Interstates symbols are a red and blue shield with the word Interstate over the red and the highway number over the blue. The interstate usually runs tangent to any town it is "linking", offering one or two exits to it. While owned and maintained by the states they run through, all Interstates are standardized to Federal standards. This means you can drive from Flagstaff in Arizona to Denver in Colorado via Albuquerque in New Mexico with the same road signs and rules of the road. (The quality of individual stretches of roads may and will vary widely, but this is due to the level of upkeep each state employs on their roads.)US 40.svg
 * A secondary system of federal highways is the U.S. Highway system. Some U.S. Highways are limited access for more or less long stretches, but they are often surface roads, sometimes with just one lane in each direction, meaning that passing other vehicles (where it's allowed at all) entails pulling over to the left into the lane used by oncoming traffic. U.S. Highways, which generally predate the Interstate system, tend to be older routes that lead through town centers. In many cases, Interstates were constructed roughly parallel to U.S. Highways to expedite traffic that wishes to bypass the cities and towns. If you don't mind stopping at traffic lights and dealing with pedestrians, U.S. Highways can lead you to some interesting off-the-beaten-path sights. U.S. Highway symbols are a white shield and a black number.
 * Each state is responsible for maintenance of the Interstates and U.S. Highways (despite the names), but each one also maintains its own system of State Highways (or State Routes) that form the bulk of the inter-community road network. State Highways are usually surface roads but may occasionally be highways; you can generally count on them being well maintained (and plowed in the winter), and following one will get you to some form of civilization sooner rather than later.
 * Many states also have county routes, which are constructed and maintained by county governments. These are almost always tertiary or at least secondary roads, they can be winding and/or unpaved, and they often go through lovely rural scenery and small towns.

Tolling
The vast majority of Interstates do not charge tolls, but several eastern states operate cross-state Interstate toll roads called Turnpikes (or the Thruway in New York), and major bridges often charge tolls as well. Cash toll booths are becoming an endangered species, with states increasingly turning to electronic tolling using a toll transponder or by taking a photograph of the vehicle's license plate and sending a bill in the mail to the vehicle owner. Tolls are levied by many different tolling agencies, each of which issues its own transponders; there is no single transponder that will cover you for all toll roads in the U.S., though some agencies have interoperability agreements with each other.

Rental agencies like to offer all-in toll plans with "convenience fees" charged per day, whether you're using toll roads or not. These rarely make sense unless you plan to use toll roads every day. It is usually cheaper, but more hassle, to pay one-off tolls (typically online) or, if renting for longer periods of time, purchasing your own toll transponder is allowed.

City driving


Most major American cities have a dense network of freeways that lead from the suburbs into the city center. These freeways are usually linked to, or even part of the interstate highway system. Outside of peak hours, driving from the outskirts of the city to the city center is usually a breeze and relatively quick. However, many of these freeways get clogged with traffic during peak hours, and it is not unheard of to be stuck in traffic for 2 hours or more. If you are planning to travel during those periods, give yourself ample time to complete the journey.

Many cities have High Occupancy Vehicle (HOV) lanes, popularly called Carpool Lanes, on some major freeways. These usually have distinctive lane markings, and a painted diamond shape in the middle of the lane every half mile or so. These lanes are limited to vehicles with multiple occupants, so they can be very beneficial to tourists. But be sure you understand how they work, since different cities implement them in different ways, even in the same state, and carpool lane violation fines are quite expensive.

In some cases this is only enforced during certain hours (this will be indicated on signs), in other areas (e.g. most of Southern California), it's 24/7. Some HOV lanes allow you to enter and exit anytime you like, others limit it to certain specific zones. A double white line means you should stay in your lane, a dashed white line allows you to enter and exit.

Major routes
The even numbered routes go west and east while the odd numbered routes go south and north:

Car rental
Car rental companies are found in every major American city, and even in many of the small towns. The big international chains such as Hertz, Avis, Enterprise, and Budget offer car rental services in the U.S. Other local chains that are not so well known internationally include Alamo, Dollar, National, Thrifty, and Action, and these are usually cheaper than the big international chains. Usually, the best deals for car rentals can be found online. Rental prices tend to be higher during major holidays, so book early if you wish to travel during peak periods. Rental cars in the U.S. have automatic transmissions, and even if you specifically ask for a manual transmission, it is impossible to get one. Similarly, Recreational Vehicle (RV) Rental services like RVShare, FlowRV and Cruise America provide Recreational Vehicles for clients who wish to rent an RV either to travel by road, or simply to enjoy the comforts of home in a location where there are no other lodging accommodations.

Rental agencies accept a valid driver's license from your country, which must be presented with an International Drivers Permit if your license needs to be translated. You may wish to join some kind of auto club before starting a large American road trip, and having a cell phone is a very good idea. Most rental agencies have some kind of emergency road service program, but they can have spotty coverage for remote regions. The largest club in the United States is the American Automobile Association (AAA) (+1-800-391-4AAA), known as "Triple A". A yearly membership runs about $60. AAA members also get discounts at many hotels, motels, restaurants and attractions; which may make it worth getting a membership even if you don't drive. Better World Club (+1-866-238-1137) offers similar rates and benefits as AAA with often timelier service and is a more eco-friendly choice (1% of revenue is donated to environmental cleanup programs). Some non-U.S. automobile clubs such as the Canadian Automobile Association (CAA), UK's Automobile Association, and Germany's ADAC have affiliate relationships with AAA that allow their members to use AAA services.

Most Americans renting cars are covered for loss or damage to the rental car either by their credit card or their own private vehicle insurance policy. Without appropriate loss/damage waiver cover, you could be liable for the entire cost of the car should it be written off in an accident. Purchasing loss/damage waiver cover and supplemental liability insurance may add up to $30/day to the price of a rental, in some cases doubling the price of the rental. If you visit the car rental website and identify your country of origin, you may be given a quote which includes the loss/damage waiver and liability insurance for considerably less. Many travel insurance policies include cover for some rental car damage – check your policy against the rental terms and conditions.

All major rental car companies prohibit smoking in rented vehicles, and will charge hefty cleaning fees to your credit card on file.

Always fill up your car's gas tank to the level it was when you received it, as companies will charge exorbitant rates (as much as $10/gallon) to top-up the tank. Some companies, such as Avis, will demand that you return the vehicle with a full tank of fuel even if it was near empty at the time you received it.

Some rental cars, primarily in the Midwest, are "flex-fuel" vehicles that can use various gasoline/ethanol mixtures, see Gasoline for details. Flex-fuel vehicles typically have a badge saying so, and run just fine on regular gas too.

If a flex-fuel vehicle has a fuel filler cap, it will always be yellow; if the vehicle has a capless fuel filler, the fueling port will be surrounded by a yellow ring.

If your car is equipped with a toll transponder, disabling it in favor of using your own or simply paying cash is almost always a better option, as many companies will charge "convenience fees" for using it, on top of the cash toll price.

Gasoline
Gasoline ("gas") is sold by the gallon, at stations that are primarily self-service (you must pump your own gas) with the exception of those in New Jersey, where self-service is illegal, and in Oregon, where stations in urban areas are required by law to provide at least 50% full-service pumps. The American gallon is smaller than the imperial gallon and equals 3.785 liters. The U.S. octane scale is different from that used in Europe; a regular gallon of U.S. gasoline has an octane rating of 87, the equivalent of about 92 in Europe. In most states, gas stations offer a choice of three levels of octane: 87 (regular), 89 (midgrade or plus), and 91 (premium). Unless you are renting a luxury vehicle, your vehicle will likely require only 87 (regular). If you are driving in the Rocky Mountains area, you may encounter stations that offer gas at lower octane ratings, most commonly 85. This is suitable for use by 87-octane vehicles at high elevations, but if you're heading for lower elevations, be sure to fill up with 87.

Diesel is not as common, but still widely used and available at most stations, especially those catering to truckers. Untaxed "offroad diesel", sold in rural areas for agricultural use, is dyed red (and sometimes referred to as "red diesel") and should not be used in cars, as there are heavy fines if you're caught.

Despite increasing petroleum prices worldwide and some increases in gas taxes, the American consumer-voter's attachment to his automobile, combined with still significant domestic oil reserves and relatively low taxes on gasoline, has kept retail fuel prices much lower than in many parts of the world. Prices fluctuate by region and season. With increasing inflation and supply-chain issues triggered by the COVID-19 pandemic and worldwide government responses to it, and subsequent disruptions stemming from the Russian invasion of Ukraine, prices as of late March 2022 average about $4.25/gallon (equivalent to $1.12/liter) for regular and about $5.15/gallon ($1.36/liter) for diesel. That said, gas prices vary dramatically from state to state, primarily based on the respective state sales and gas tax rates (which are invariably included in the advertised price). The highest prices are usually found in Hawaii, Alaska, the West Coast (especially California), Illinois, and New York City. The lowest are generally found in the south central U.S. Fuel prices also vary seasonally; all other things being equal, gasoline is at its cheapest during the winter months (when people tend to take fewer long trips), while diesel is at its most expensive during those same months (due partly to the wide use of heating oil, very similar to diesel, in the northeastern states). A good rule of thumb to find cheaper gas is to venture away from the highway and city centers. Additionally, warehouse clubs such as Costco and Sam's Club frequently sell gas (and, depending on the location, diesel) at somewhat lower prices than most stations in their immediate areas, though only to the club's members. Various mobile apps and websites (such as GasBuddy) display cheapest current fuel prices within each local area.

Gas prices almost always have an extra nine-tenths of a cent added to them. This price will be noted on gas station signs and pumps, usually as $4.499, for example, however the extra nine-tenths of a cent is usually not spoken, the previous example would be read as "four forty-nine."

Though less prevalent than in the early 2010s, some rental cars (and cars sold to the public) are "flex-fuel" vehicles; as noted above, they can operate on any mixture of gasoline and ethanol ranging from pure gasoline (E0) to 85% ethanol/15% gasoline, commonly known as E85 (although under U.S. regulations, fuel with ethanol content between 51% and 85% can be legally sold as "E85"). Although only about 3% of the fuel stations in the U.S. sell E85, it is increasingly available throughout the country, especially in the midwestern states. Depending on the location, E85 may be significantly cheaper than regular gasoline (which is most often E10). However, this cost advantage is frequently more than offset by reduced fuel efficiency when operating on E85. Many flex-fuel vehicles see a 20–25% reduction in efficiency when running on E85 as opposed to regular. However, this may vary according to how a vehicle's engine is tuned from the factory, as well as the exact composition of "E85" sold. (Winter blends of E85 are most commonly 70% ethanol instead of 85%.)

Parking
In many cities, curbs are painted to reflect the ability to park at a particular location. The colors used and the meaning of the colors used varies from city to city. In general, red (and sometimes yellow) means "no parking" and blue designates handicapped parking only (with an appropriate license plate or placard). In California, yellow curbs designate loading only (goods/cargo), white designates passenger pickup or dropoff, and green indicates there is a time limit for parking (look at signs for time limit). Elsewhere, the meaning of curb colors varies. Always follow parking signs and, if you are uncertain whether parking is allowed at a particular spot, it's best to park elsewhere than receive a parking ticket or even have your vehicle towed and impounded (which will result in a large fee to retrieve). A parked vehicle should never block a crosswalk, fire hydrant, or the entrance to a driveway/alley.

Parking garages or parking ramps (UK: car parks) are found in every major American city, though prices can be somewhat expensive in the larger cities, with prices going as high as over $50 a day in New York City. Street parking is available in most of the small towns, but in some larger cities may be reserved for residents of those areas only. Fines for illegal parking are stiff, and in some cases, your vehicle might even be towed away.

Visitors to New York City, Boston, Chicago, Washington D.C. and San Francisco should seriously consider leaving their car in a garage and use public transportation, bikes, or their feet to get around the city.

Itineraries
Driving in the United States helps you to traverse the wonders the United States has to offer, from nature to culture and history. Sites such as the Grand Canyon, Yellowstone National Park, Yosemite National Park, and Mount Rushmore are at best reached and enjoyed by car; taking an airplane will still require more than an hour's drive to get there! For visiting multiple sights, look at the itineraries below for an idea of what a specific stretch of the United States' roads is famous for:
 * Alaska Highway
 * Driving between the contiguous United States and the Alaska Highway
 * Dalton Highway
 * A Taste of Coastal Texas
 * Buffalo-Pittsburgh Highway
 * Craft Brewery Tour of Southwest Wisconsin
 * Braddock Expedition
 * El Camino Real
 * Interstate 5 (Old US Highway 99)
 * Interstate 10 (Old Spanish Auto Trail on US 90)
 * Lincoln Highway (US Highway 30)
 * Mountain Loop Highway
 * Natchez Trace Parkway
 * The North Cascade Loop
 * Oregon Trail
 * Pacific Coast Highway (California State Route 1 and US Highway 101)
 * Route 66 and Radiator Springs
 * The Jazz Track
 * U.S. Highway 1
 * Easy Rider
 * Bandit Run, inspired by Smokey and the Bandit
 * Pan-American Highway

Stay safe
When driving in rural areas, particularly in the national parks, be on the lookout for wildlife on the road, especially at dawn or dusk when they are most active, and the risk of animal collisions is the highest. Deer are the most common wildlife you are likely to encounter, but you may also encounter bears, bison, moose or other large wild animals.