Yamhill County is part of the the Chehalem Mountains AVA wine region, which sits on a series of sedimentary ridges that provide diverse soils and growing conditions at slightly higher altitudes than other Willamette Valley vineyards. Some 150 vineyards are located throughout the hilly countryside, comprising three counties—Yamhill, Washington and Clackamas—which frame the southwestern suburbs of the Portland metropolitan area. Land for sale in Oregon's Yamhill County recently totaled nearly $214 million and nearly 4,000 acres. Yamhill County ranks 13th in the Beaver State for the combined amount of land currently advertised for sale. Mcminnville had the most land for sale. Yamhill County is the 32nd largest county (718 square miles) in Oregon. It's located in the Northwest Oregon region of the state.