Interstate Highway Bridge, Vertical-lift road bridge between Nez Perce County and Asotin County, United States.

The Interstate Highway Bridge is a 1,424-foot (434 m) vertical-lift road bridge over the Snake River between Clarkston, Washington and Lewiston, Idaho. It carries U.S. Route 12 across the state line and is maintained by the Washington State Department of Transportation. Locals call it the "Blue Bridge" for its blue-painted steel.

The bridge was completed in 1939 to meet the growing need for reliable transportation between Idaho and Washington during the early twentieth century. Its construction addressed the economic necessity of establishing a stable link between the two states.

The bridge serves as a daily crossing point where residents and travelers from Idaho and Washington meet and interact during their journeys. It represents a practical link between two communities whose local economies and social connections depend on regular movement across the river.

The bridge carries US 12 over the Snake River between Clarkston and Lewiston and is maintained by the Washington State Department of Transportation. Drivers cross the state line mid-span; the deck is 1,424 feet (434 m) long. The Southway Bridge, built in the 1980s, now takes much of the through traffic, so this crossing is often the quieter option.

Locals call it the "Blue Bridge," a nickname tied to its painted steel. Until the Southway Bridge opened in the 1980s, it was the main crossing between Lewiston and Clarkston, so the older span carried nearly all traffic between the two towns for four decades.