100% estate grown. In 1968, inspired by the belief that great wines come from great vineyards, our family established Trefethen Vineyards in the Oak Knoll District of Napa Valley. Ever since, we have handcrafted our wines exclusively from our estate-grown grapes. Our beautifully aromatic Dry Riesling, with its crisp apple, citrus and mineral flavors, reveals classic Napa Valley quality. We proudly practice sustainable farming. 13% alc./vol.