U.S. Route 20

U.S. Route 20 or U.S. Highway 20 (US 20) is an east–west United States highway that goes from Newport, Oregon to Boston, Massachusetts. The highway is 3,365 miles (5,415 km) long. It is the longest road in the United States.^[1]

U.S. Route 20
US 20 highlighted in red
Route information
Length	3,365 mi[1] (5,415 km)
Existed	November 11, 1926[2]–present
Major junctions
West end	US 101 in Newport, OR
Major intersections	I-5 at Albany, OR I-15 at Idaho Falls, ID I-25 at Casper, WY I-35 near Williams, IA I-55 at Hodgkins, IL I-65 / I-90 in Gary, IN I-75 in Perrysburg, OH I-79 near Erie, PA I-87 / I-90 near Albany, NY I-95 in Waltham, MA
East end	Route 2 in Boston, MA
Location
Country	United States
States	Oregon, Idaho, Montana, Wyoming, Nebraska, Iowa, Illinois, Indiana, Ohio, Pennsylvania, New York, Massachusetts
Highway system
United States Numbered Highway System List Special Divided

There is a gap in the official signage of US 20 through Yellowstone National Park. The park uses unnumbered roads.