About Pierce County
Beginning at the islands and channels in the southern tip of the Puget Sound, Pierce County includes miles of the heavily populated coastal plains, the forested slopes of the Cascade Mountains, and the towering peak of Mount Rainier.
Being part of the Seattle metropolitan area, which extends all along the eastern shore of the Puget Sound, the county has a population of 700,820, as of the year 2000. Tacoma is the county seat and largest city. Pierce County covers 1,806 square miles, including 128 square miles of water. Interstate 5 crosses the northwest edge of the county, staying close to the coast. Washington Highways 7 and 161 pass through the county southward from Tacoma. Washington Highways 706 and 410 climb into the mountains and up to Mount Rainier.