The Willamette River flows the entire length of the valley, which is surrounded by mountains on three sides-the Oregon Coast Range to the west, the Cascade Range to the east, and the Calapooya Mountains to the south.
The Willamette River flows the entire length of the valley-the Oregon Coast Range to the west, the Cascade Range to the east, and the Calapooya Mountains to the south. The valley is surrounded by mountains on three sides.