What are the top 5 longest roads in the US?

Top 5 Longest Roads in the US: Route 20 vs US 6

Discovering Americas most expansive transportation corridors reveals the monumental engineering feats connecting distant coasts. Exploring these legendary cross-country routes highlights the vast scale of the national highway network and provides essential insights for long-distance travel planning across diverse landscapes.

What are the top 5 longest roads in the US?

The top 5 longest roads in the US are U.S. Route 20, U.S. Route 6, U.S. Route 30, Interstate 90, and U.S. Route 50. Leading the pack is U.S. Route 20 at approximately 3,365 miles.

Most road trip guides tell you to stick to the Interstates for cross-country travel. But there is one counterintuitive factor about taking these older routes that most travelers completely overlook - Ill explain it when we discuss navigability through places like Yellowstone later on.

Confusion between U.S. Numbered Highways and the Interstate Highway System rankings

This confusion trips people up constantly. The United States Numbered Highway System was created in 1926. These are the older, surface-level roads that often run right through city centers. The Interstate Highway System came later in 1956. These are the high-speed freeways.

When people ask what is the longest road in america, they often assume it must be a massive Interstate. Rarely do they realize that the top three longest roads are actually the older U.S. routes. Interstates prioritize direct paths. U.S. highways meander.

Detailed Breakdown: The Top 5 Longest Highways in the US

1. U.S. Route 20

U.S. Route 20 is the longest highway in the united states, stretching from Boston, Massachusetts to Newport, Oregon. The route crosses 12 different states and covers approximately 3,365 miles. It is a staggering distance.

Driving the entirety of U.S. Route 20 usually takes upwards of 70 to 80 hours of pure driving time due to lower speed limits. Keep in mind that traffic volume varies wildly - some rural stretches see very few cars, while urban areas experience heavy congestion.

2. U.S. Route 6

Known as the Grand Army of the Republic Highway, U.S. Route 6 runs from Provincetown, Massachusetts to Bishop, California. Historically, it stretched all the way to Long Beach. It traverses 14 states. That is a lot of ground.

If you are wondering how long is us route 6 length miles, the current alignment sits at about 3,207 miles. It was once the longest road in the country before state-level realignments shortened its western path.

3. U.S. Route 30

U.S. Route 30 follows a large part of the historic Lincoln Highway - Americas first transcontinental road. It runs from Atlantic City, New Jersey to Astoria, Oregon. The highway passes through 11 states. History lives here.

Many sections of this road still feature the original concrete markers from the early 1900s. It remains a vital route for local freight and regional travel, stretching for roughly 3,112 miles across the nation.

4. Interstate 90

Interstate 90 is the longest interstate highway in the us. It connects Seattle, Washington to Boston, Massachusetts. The freeway crosses 13 states. Fast and efficient.

Unlike the older U.S. routes, I-90 is designed exclusively for high-speed travel. Running approximately 3,020 miles, it serves as a major commercial freight corridor. A typical cross-country trip on Interstate 90 usually takes about 45 to 50 hours of pure driving time.

5. U.S. Route 50

Running from West Sacramento, California to Ocean City, Maryland, U.S. Route 50 crosses 12 states. It spans about 3,011 miles. People call its Nevada section The Loneliest Road in America. Period.

The Nevada stretch traverses vast swaths of barren terrain with very few signs of human civilization. Lets be honest - you do not take this road if you are in a hurry.

Concerns regarding road quality or navigability through famous spots like Yellowstone

Here is that counterintuitive factor I mentioned earlier: sometimes these massive highways literally lose their identity. When U.S. Route 20 enters Yellowstone National Park, it becomes completely unnumbered. The official highway designation officially pauses at the east entrance and resumes at the west entrance.

When I first attempted a cross-country drive, I made every rookie mistake possible. I assumed U.S. Route 20 would be like driving on an Interstate and planned to cover 600 miles a day. Reality hit hard. I spent three days stuck behind tractors in rural areas and crawling through local town traffic. It took me 48 hours to realize that older highways require patience. My hands were cramping from gripping the steering wheel while navigating tight, winding mountain passes.

Road quality on these older routes varies significantly. You might find a smooth, four-lane divided highway in one state, and a bumpy, two-lane rural road in the next. Be prepared for sudden speed limit changes.

Uncertainty about whether Route 66 is still among the longest roads

Many people wonder if the famous Route 66 belongs on this list. It doesnt. Route 66 was officially decommissioned from the United States Highway System in 1985.

Even at its peak length of roughly 2,448 miles, it would not have cracked the top five. While parts of it are preserved as a scenic byway, it is no longer a continuous, functional U.S. Highway. The nostalgia is real, but the mileage just does not stack up against heavyweights like U.S. Route 20.

Highway Comparison: U.S. Routes vs. Interstates

Understanding the difference between these two systems is crucial for planning any massive road trip.

U.S. Numbered Highways

• Open access with frequent traffic lights and pedestrian crossings

• Variable speed limits, often dropping to 25 mph in towns

• Built to connect city centers and local main streets directly

Interstate Highway System

• Controlled access via on-ramps and off-ramps only

• Consistently high speed limits, typically 65 to 80 mph

• Built for high-speed, long-distance travel and commercial freight

Hanh's Cross-Country Reality Check

Hanh, a student from Hanoi studying in Boston, wanted to experience an American road trip. She decided to drive U.S. Route 20 to Oregon, assuming she could finish the 3,365-mile journey in five days.

Her first attempt failed miserably. By day two, she was constantly stopping at traffic lights in small towns. The stop-and-go driving left her exhausted.

The breakthrough came when a local explained that older routes are not freeways. She realized she needed to adjust her expectations and treat the drive as a scenic tour.

She extended her trip to 14 days. By driving fewer hours and stopping at landmarks, she turned a stressful commute into a memorable adventure.