Lewiston is a city and the county seat of Nez Perce County, Idaho, United States, in the state's north central region. It is the second-largest city in the northern Idaho region, behind Coeur d'Alene, and ninth-largest in the state. Lewiston is the principal city of the Lewiston, ID-WA Metropolitan Statistical Area, which includes all of Nez Perce County and Asotin County, Washington. As of the 2010 census, the population of Lewiston was 31,894, up from 30,904 in 2000.
Lewiston is located at the confluence of the Snake River and Clearwater River, thirty miles (50 km) upstream and southeast of the Lower Granite Dam. Because of dams (and their locks) on the Snake and Columbia River, Lewiston is reachable by some ocean-going vessels. The Port of Lewiston (Idaho's only seaport) has the distinction of being the farthest inland port east of the West Coast. The Lewiston-Nez Perce County Airport serves the city by air.
Lewiston was founded in 1862 in the wake of a gold rush which began the previous year near Pierce, northeast of Lewiston. In 1863, Lewiston became the first capital of the newly created Idaho Territory.