Take a Classic Road Trip on America's Longest Highway (2024)

An aura of history and romance surrounds famous highways like Route 66. Modernization, as well as the pursuit of convenience and safety, have led to more four- or eight-lane highways crisscrossing the nation, like I-90, I-35 or I-94. Finite stretches of state and county roads may still have that timeless two-lanes-cutting-through-the-countryside appeal, but road trips that follow the cross-country highways of yesteryear mostly take place in people’s imagination, not on the blacktop.

However, there is one historic highway where it is still possible to get in touch with the glory days of the American road trip. U.S. Route 20 covers 3,365 miles from Boston, Massachusetts, to Newport, Oregon. It is currently the longest highway in the country. For most of its length, Route 20 runs roughly parallel to I-90, which connects Boston and Seattle (a distance of 3,100 miles).

History of Route 20

Route 20 officially became a U.S. highway in 1926, and during its early years, it terminated at Yellowstone National Park. It was extended westward in 1940, before reaching its current length in 1960. Since U.S. numbered highways are not designated within National Parks, Route 20 technically does not run through Yellowstone; it stops at the park's eastern entrance and restarts at the western entrance. This had led some people to say it is not the longest “continuous” highway in the country, instead, they prefer to give the nod to 3,205-mile Route 6. But the U.S. Department of Transportation confirms that indeed, Route 20 is considered the longest.

Sections of Route 20 have been upgraded over the years, but many parts provide the setting for a two-lane trip to the past, and a few states and organizations are actively trying to retain the highway in its historic condition. Whether you are a road-trip purist or someone seeking to check “driving the longest highway in the U.S.” off of a bucket list, Route 20 holds innumerable possibilities. The road allows you to come face-to-face with some of the most famous cities, charming towns, and scenic landscapes in the country.

The Highway's Course

Route 20 passes through Massachusetts, New York, Pennsylvania, Ohio, Indiana, Illinois, Iowa, Nebraska, Wyoming, Montana, Idaho and Oregon. It includes stops in Boston, Toledo, Chicago, Gary, Sioux City, Casper, Boise and two different cities named Albany (one in New York and the other in Oregon).

In Massachusetts, part of Route 20 follows the path of the old Boston Post Road, which was used to carry mail between Boston and New York City in the 17th and 18th centuries. In New York state, the scenic Finger Lakes, Lake Erie, and the beautifully rugged rural landscapes of central New York offer the kind of classic roadside sightseeing that many drivers dream about. Erie is also part of the scenery in Pennsylvania and Ohio. Throughout its easternmost quarter, Route 20 passes through a number of “frozen in time” small towns whose Main Streets have changed little since the 1950s.

As Route 20 continues west, it passes the famous Indiana Dunes National Lakeshore before offering a glimpse of another face of America: heavily industrialized cities like Gary, Indiana, and the overly urbanized landscapes of the South Side of Chicago. In Iowa and especially Nebraska, drivers will find the kind of flat, wide-open spaces that many consider a necessary element of a classic American road trip.

The beauty of rural Wyoming and Yellowstone National Park highlight the rest of the original “eastern” section of the highway. As we've already mentioned, U.S. 20 terminated at Yellowstone until 1940, when the “western” portion was added. Thus, U.S. 20 in Wyoming is still considered part of the “eastern” section.

After restarting on the other side of the famed national park, the road takes a brief cut through Montana before moving to Idaho, with stops in Boise, the otherworldly landscapes of Craters of the Moon National Monument and the beautiful Lost River Range.

Finally, in Oregon, Route 20 crosses the Cascades and the Oregon High Desert before moving through the remote Central Coast Range and the vineyards of the Willamette Valley. It terminates less than a mile from the Pacific.

Whether you are seeking two-lane romance or just trying to hit as many attractions as possible during your drive, Route 20 remains an ideal option for an epic American road trip.