The Yamhill-Carlton AVA is an American Viticultural Area located in both Washington County and Yamhill County, Oregon. It is entirely contained within the Willamette Valley AVA, and surrounds the towns of Carlton and Yamhill. The mountain ridges surrounding the AVA form a horseshoe shape, and most of the vineyards are located on south-facing slopes. The AVA includes only land between 200 feet (61 m) and 1,000 feet (305 m) above sea level where marine sediments are some of the oldest soils in the Willamette Valley and create unique conditions for viticulture. The region is in the rain shadow of the 3,500 feet (1,100 m) Oregon Coast Range, a short distance to the west.