Racking up miles is the bread and butter of any truck fleet service: through the course of a typical delivery a driver might cross various states, cities, counties, and highways. However, it’s possible to log some seriously long trips without using more than one highway. Below is a summary of the five longest highways in the US. 

US 20

This east-west highway (fyi: routes with numbers that end in a 0 run from coast-to-coast), has an eastern terminus in Boston, Massachusetts in Kenmore Square, and a western terminus in Newport, Oregon. Although there is a small discontinuity when it crosses Yellowstone National Park, it is the longest road in the US with a total mileage of 2,542. 

While US 20 now stands as the king of highways in the US, it wasn’t always the case. Changes to other highways (more on that later), plus an extension to US 20 in 1940, turned US 20 into the longest road. Prior to 1940, it ended at the eastern entrance of Yellowstone Park. US 20 crosses 12 different states in all: Massachusetts, New York, Pennsylvania, Ohio, Indiana, Illinois, Iowa, Nebraska, Wyoming, Montana, Idaho, and Oregon. 

US 6

Before US 20 took over as the longest road in the US, that honor belonged to US 6, also called the Great Army of the Republic Highway. Its current eastern terminus is Provincetown, Massachusetts, and its western terminus is Bishop, California, giving it a total mileage of 3,198.87. From 1936 to 1964, its western terminus was Long Beach, California. It was at this time that it held the title as the longest highway in the US. 

US 6 crosses through California, Nevada, Utah, Colorado, Nebraska, Iowa, Illinois, Indiana, Ohio, Pennsylvania, New York, Connecticut, Rhode Island, and Massachusetts. 


Although third in length overall, I-90 is the longest highway in the interstate system and has existed since 1956. Its total length of 3,020.54 miles takes drivers from its western terminus in Seattle, Washington to its eastern terminus in Boston, Massachusetts. Along the way, it crosses Idaho, Montana, Wyoming, South Dakota, Minnesota, Wisconsin, Illinois, Indiana, Ohio, Pennsylvania, and New York. 

The town of Wallace, Idaho prides itself as having the last stop light on the I-90 in the Rocky Mountains. I-90 was rerouted around Wallace in 1991 to prevent the interstate highway from crossing through its many historical downtown buildings. 

US 30

U.S. Route 30 has existed since 1926 and spans 3,073 miles on its trip from Astoria, Oregon to Atlantic City, New Jersey. US 30 absorbed much of the first road across America, the Lincoln Highway. The road crosses through: Oregon, Idaho, Wyoming, Nebraska, Iowa, Illinois, Indiana, Ohio, West Virginia, Pennsylvania, and New Jersey. 

The section of US 30 between Bliss and Buhl, Idaho is referred to as the Thousand Springs Scenic Byway. This 62 mile stretch, which can be completed in about two hours and four minutes, takes its name from the streams and rivulets that come from the Snake River Plains Aquifer. These days, hydroelectric projects divert some of the water, and while there may not be thousands of springs visible along the road, it is still an impressive sight for drivers. 

The road’s original plan was to go from Salt Lake City, Utah to Atlantic City, New Jersey. This plan had to be changed and US 30 rerouted various times largely because of the objections from Idaho and Oregon. 

US 50

The last entry on the list, US Route 50, has existed since 1926 and travels from West Sacramento, California to Ocean City, Maryland. It has a total mileage of 3,008. Along the road, it crosses 12 states and also the District of Columbia: California, Nevada, Utah, Colorado, Kansas, Missouri, Illinois, Indiana, Ohio, West Virginia, Virginia, and Maryland.

The section through Nevada of US 50 has come to be known as “The Loneliest Road in America” because on this stretch, your most common companions will be mountains, sand, and lots of sky, instead of the usual signage and truck stops. This name was given to the Nevada section of US 50 in 1986 by Life magazine

Keep Your Fleet Clean After Many Miles

After all those miles, whether it’s on one road or many, your trucks will definitely need some maintenance and cleaning. Fleet Clean USA in Dallas, TX offers on-site fleet services to help get your fleet good as new. Exterior washes, trailer washouts, internal cleaning, and internal steam detailing can all be done at your location, meaning virtually no disruption to your operations. Looking for more information? Contact us today for a free quote on on-site fleet services in Dallas, TX