Book a tour at Ferrari-Carano, and you won't be disappointed. Boasting one of the most opulent winery grounds in the Dry Creek Valley, the garden and chateau are worth the price of admission alone, not to mention the fabulous wines. While not technically a free tasting experience, they will waive tasting fees with a purchase, depending on which tour you take.
The West Face and Reserve Cabs are incredible, and can only be tasted downstairs in the Enoteca Reserve Wine Tasting Bar.
Head north or south on Hwy 101 toward Geyserville, depending on where you are coming from, and take the Geyserville Hwy 128 exit (512). Head west on Canyon Road to Dry Creek Road and turn right. Proceed for a couple of miles until you reach the winery.