U.S. Route 10 or U.S. Highway 10 (US 10) is an east–west United States highway formed in 1926. Though it never became the cross-country highway suggested by the "0" as the last digit of its route number, US 10 was one of the original long-haul highways, running from Detroit, Michigan, to Seattle, Washington, but then losing much of its length when new Interstate Highways were built on top of its right-of-way. In 2010, its length was .