Tuscany is renowned for complex red wines made chiefly from the Sangiovese grape, brought to America by Italian immigrants in the late 19th century but arguably most enjoyed at home in Tuscany. At Poggio Antico, about five miles outside Montalcino, and Tenuta Valdipiatta, near Montepulciano, the tours are free, although sampling the full range of wine costs about $25.

Poggio Antico's 80 acres of vineyards, winery and restaurant sit atop a ridge reached by a curving, cypress-lined drive. Our guide, a young Italian woman who had studied grape cultivation at the University of California, Davis, took us into the fermentation room and the cellar, explaining how the estate produces its prized Brunello, the wine that made the Montalcino region famous. State-certified Brunello bears a seal, attesting its production by a strict set of rules. A Brunello di Montalcino must be made of 100 percent Sangiovese grapes, aged for at least four years (including two years in oak casks) and bottled in the Montalcino area. Young Brunello is called "Rosso di Montalcino" and is about half as expensive as the older vintage. We sampled five Poggio Antico wines at a counter in the tasting room, including a memorable red-brown 2003 Brunello di Montalcino ($42 per bottle) and a fine Rosso ($22).

From there, we drove on to the lovely Tuscan hill town of Montepulciano and stayed at the four-room Locanda San Francesco, run by Cinzia Caporali, the daughter of a local vintner. She arranged a tour for us at Tenuta Valdipiatta, a small, homey winery started by her father in the late 1980s and now managed by another Caporali daughter, Miriam.

The winery in a valley below Montepulciano is surrounded by 70 acres of vineyards, planted mostly with Sangiovese grapes with a smattering of merlots, cabernet sauvignons and pinot noirs. These are mixed with Sangioveses to yield special homemade varieties such as Tenuta Valdipiatta's Trefonti.

Joined by the winery's founder, Guilio Caporali, and his two golden retrievers, he shared with us the winery's Latin motto: "Licet sitis sine siti," which, when translated, suggests you don't have to be thirsty to drink.