From the other side of the world: New Delhi, India has non-stop service to New York (via JFK and Newark airports) and to Chicago. Mumbai has non-stop flights to New York (JFK and Newark). From Pakistan, Saudi Arabia, Uzbekistan and United Arab Emirates you can also fly to New York (JFK). Qatar, and Saudi Arabian fly to Washington, D. C. , and South African Airways goes to New York (JFK) and Washington, DC (Dulles). Los Angeles, Dallas, and Houston both offer non-stop service to Qatar and the United Arab Emirates.
The quickest and often the most convenient way of long-distance intercity travel in the US is by plane. Coast-to-coast travel takes about six hours from east to west, and five hours from west to east, compared to the three or four days necessary for land transportation.
One major scenic long-distance train route, the California Zephyr, runs from Emeryville in the Bay Area of California to Chicago, via Reno, Salt Lake City and Denver. The full trip takes around 60 hours, but has incredible views of the Western deserts, the Rocky Mountains, and the Great Plains, things that you just cannot see if you fly. Many of the sights on this route are simply inaccessible to cars. The trains run only once per day, and they usually sell out well in advance.
Amtrak's single most popular long-distance train is the Chicago-Seattle/Portland "Empire Builder" train via Milwaukee, St. Paul/Minneapolis, Fargo, Minot, Glacier National Park, Whitefish, and Spokane.
Bradt's USA by Rail book (ISBN 9781841623894) is a guide to all Amtrak routes, with maps, station details and other practical advice.
Stagecoach Group owns & operates Coach USA and Megabus. They offer inexpensive daily bus service departing from curbside bus stops in various parts of the country: the entire East Coast from Maine to Florida and as far west as California and Nebraska (and to Canada) from several hub cities.
Chinatown buses also provide curb-side departures for a standard walk-up cash fare often much lower than other operators' fares. These lines operate through the East Coast down with some further out destinations in the Midwest, the South, and along as along the West Coast.
Many Americans will tell you that you can't see the "real" America except by car. In addition, many of the country's major natural attractions, such as the Grand Canyon, are in rugged landscapes and environments, and are almost impossible to get to without an automobile. If you have the time, a classic American road trip with a rented car is very easy to achieve and quite an adventure. Just keep in mind that because of the distances, this kind of travel can mean many hours, days, or even a week behind the wheel, so pay attention to the comfort of the car you use.
The United States is covered with a convenient system of Interstate Highways. These roads connect all of the major population centers, and they make it easy to cover long distances—or get to the other side of a large city—quickly. These highways cross the entire US mainland from the Atlantic to the Pacific, through several time zones, landscapes, and even climates. Most of these highways have modern and safe state run "rest stops" or "traveler service" areas. These rest stops offer fuel, food, restrooms, and phone service. Some of the larger resort areas have massive "service areas", with hundreds of hotels, restaurants, auto service, and other services. Many of these rest stops also offer tourist information, vending machines, and a picnic areas.
Posted speed limits can range from as low as 45 miles per hour (70km/h) in densely urban areas to as much as 85mph (135km/h) in rural stretches of Texas, but mostly they'll be between 65 and 75mph (105–120km/h). The speed limits (in miles per hour) are always clearly posted on Interstates.