Theorem Vineyards spans 60 acres of hillside land on the north slope of Diamond Mountain in Calistoga, 1,100 feet above sea level. Because of our unique location, we’re blessed with little fog, abundant direct sunlight and a porous volcanic soil that heats and cools quickly.

The property is divided roughly into thirds: Twenty acres devoted to vines, a 20-acre forest of redwood and Douglas firs, and twenty pastoral acres for the winery, house and barns.

We grow mostly Cabernet Sauvignon, a little more than half of which are old vines, and a small amount of Merlot. All of our grapes are harvested by hand, a process that’s in keeping with the Theorem philosophy, that great wine comes from being close to the land.