Boise is the capital and most populous city of the U.S. state of Idaho as well as the county seat of Ada County. Located on the Boise River, this is the most populated city of the Boise City-Nampa metropolitan area and the largest city between Salt Lake City, Utah and Portland, Oregon. As of the 2010 Census Bureau, Boise's city population was 205,671, making it the fourth largest city in the American Pacific Northwest. The Boise metropolitan area is estimated to have 585,207 inhabitants, by far the most populous metropolitan area in Idaho. It is also the 98th largest US city by population.