Clarkston
Market InsightsClarkston is a city in Asotin County, Washington, United States. It is part of the Lewiston metropolitan area, and is located west of Lewiston, Idaho, across the Snake River.The population of Clarkston was 7,229 in 2010 census.Walla Walla Community College opened a branch campus in Clarkston that serves the surrounding area.With a ZIP code of 99403, Clarkston has the highest zip code of any area in the contiguous United States.