The Tri-Cities is a mid-sized metropolitan area in the southeastern part of the U.S. state of Washington, consisting of three neighboring cities: Richland, Kennewick, and  Pasco. The cities are located at the confluence of the Yakima, Snake, and Columbia rivers in the semi-arid region of Southeastern Washington. A fourth neighboring city, West Richland, is generally included as part of the Tri-City area and region, as are a handful of unincorporated communities. Each city borders either another city or one of the area's rivers, making the Tri-Cities seem like one uninterrupted mid-sized city.