Tanasbourne, Oregon is a neighborhoo in Washington County, Oregon where NW 185th Avenue and U.S. Route 26 intersect. The area sits between Beaverton and Hillsboro, and is generally considered to be south of US 26, north of Walker Road, west of 158th, and east of Cornelius Pass Road. The area has many shopping areas and is the former home of the now defunct Tanasbourne Mall.