Washington County is one of 36 counties in the U.S. state of Oregon. Originally named Twality when created in 1843, the territorial legislature renamed it for the first president of the United States, George Washington, in 1849. The original boundaries included the entire northwest corner of Oregon before sections became new counties. Washington County contains only one river, the Tualatin River, and its drainage basin is almost entirely within t...
more
Washington County is one of 36 counties in the U.S. state of Oregon. Originally named Twality when created in 1843, the territorial legislature renamed it for the first president of the United States, George Washington, in 1849. The original boundaries included the entire northwest corner of Oregon before sections became new counties. Washington County contains only one river, the Tualatin River, and its drainage basin is almost entirely within the county. The county is nearly conterminous with the Tualatin Valley and is bordered on the west and north by the Northern Oregon Coast Range, on the south by the Chehalem Mountains, and on the north and east by the Tualatin Mountains (or West Hills).
In 2000 census, its population was 445,342. As of 2008, the estimate is 519,925, making it the second most populous county in the state. The seat and largest city is Hillsboro. Other cities include Beaverton, Tigard, and Forest Grove, the oldest city in the county. Major roads in the county...
less
