U.S. Route 101
The nearly highway's northern terminus is in Tumwater, Washington: the route remains along the Olympic Peninsula's coastal perimeter west, north, and east; the northernmost point on the highway is in Port Angeles. The southern terminus of US 101 is in Los Angeles at the East Los Angeles Interchange, the world's busiest freeway interchange.
U.S. Route 81
Its southern terminus is in Fort Worth, Texas, at an intersection with Interstate 35W. Between the inception of the numbered highway system in 1926 through 1991, US 81's southern terminus was at the Mexican border in Laredo, Texas. In 1991, the terminus was moved to San Antonio. The route was shortened to its present length of in 1993, when the terminus was moved to Fort Worth. In both cases, the dropped portions of US 81 were replaced by Interstate 35. Portions of former US-81 south of Fort Worth continue to exist as business loops of I-35; a section from Hillsboro to Fort Worth exists as State Highway 81.