Grey Stack Cellars gets its name from the Grey Stacks of volcanic blue shale rocks from the ancient volcanoes in the area between Santa Rosa and Glen Ellen.  Some of these Grey Stacks pre-dated the cattle ranchers who later used them to mark their fields and can be found throughout the Bay area.  Patrick Sullivan, Grey Stack Cellars Owner and Winemaker, grew up in this area known as Bennett Valley and makes wines from his family’s estate called Four Brothers Vineyard.