Bagno Vignoni, known for its thermal baths and spas, is a hamlet in the rolling hills southwest of Siena in the quintessential Tuscan countryside of post cards and movies. Like a lot of small towns in this country it has been brought back to post-war life and is fully set up to exploit the tourism trade with ample parking, hotels (Albergo Le Terme, Hotel Posta Marcucci), and fancy places to eat (Osteria del Leone). Even so, it still retains a lot of charm and is one of those places you eventually have to see, especially for the large pool in the center of the town that has been used since Roman times. The film Nostalghia by Andrei Tarkovsky features the pool prominently, although when it was in a much worse state of repair (the film was shot in 1983). Here is a good map of the village, and this page has some additional information too.