The Guenoc Valley Vineyard is located within the Guenoc Valley AVA and the heart of Langtry Farms. The Guenoc Valley AVA was established in November 1981 which was ten months after the Napa Valley AVA was established. The Guenoc Valley AVA was California’s first single proprietor appellation.

The vineyard is 260 acres at an elevation of 1,000 feet and is planted to Petite Sirah, Chardonnay, and Sauvignon Blanc. The Guenoc Valley Vineyard produces exceptionally high quality fruit as a result of its alluvial soils generated by Bucksnort Creek and its cool nights and warm days. Diurnal temperature ranges can reach 50 degrees in a twenty-four hour period.