The Yorkville Highlands received its designation as an AVA in 1998. Located in southern Mendocino County, California the Yorkville Highlands separate Sonoma County's Alexander Valley AVA from Mendocino County's Anderson Valley AVA. The soil in the Yorkville Highlands is rocky with high gravel content, which provides excellent drainage. During the day, the climate is cooler than Alexander Valley but warmer than Anderson Valley while at night the highlands are cooler than the surrounding areas. The Yorkville Highlands produce world-class Pinot Noir.