Cascade Locks is a city in Hood River County, Oregon, United States. The city took its name from a set of locks built to improve navigation past the Cascades Rapids of the Columbia River. The U.S. federal government approved the plan for the locks in 1875, construction began in 1878, and the locks were completed on November 5, 1896. The locks were subsequently submerged in 1938, replaced by Bonneville Lock and Dam, although the city lost no land from the expansion of Lake Bonneville behind the dam some 4 miles downstream of the city. The city population was 1,144 at the 2010 census.Cascade Locks is just upstream from the Bridge of the Gods, a toll bridge that spans the Columbia River. It is the only bridge across the Columbia between Portland and Hood River. Cascade Locks is a few miles upstream of Eagle Creek Gorge, a popular scenic area that doubles as an alternate route for the Pacific Crest Trail.