The Calistoga AVA, named for the eponymous town, is situated in northern Napa Valley, not far from the border with Sonoma. This is among the warmest zones in all of Napa Valley, with temperatures sometimes reaching 100 degrees during the day at the valley floor. The combination of cool nights and breezes from the nearby Chalk Hill gap help preserve acidity in the grapes. Soils are a combination of gravel, bedrock and silt, with volcanic content; the percentage of volcanic content in Calistoga soils is the highest in Napa Valley. Vines are planted between 300 and 1200 feet. Red varieties dominate, especially Cabernet Sauvignon, Merlot and Cabernet Franc. The best examples of Calistoga reds are full-bodied with firm tannins and a distinct minerality in the finish. Generally, these reds need time in the bottle before displaying their best qualities; they age well for a decade or two. (Wine/Appellations)