The Caldeiras da Vila are the fumaroles in the middle of Furnas itself — boiling mud, sulphurous steam, springs of hot mineral water rising directly out of the ground in a small public park a few minutes' walk from the main square. They are a different experience from the larger caldeiras at the lake: less dramatic but more immediate, with the surreal feeling that an active volcano is being treated as a piece of municipal landscaping.
Each spring has a sign indicating which mineral it is rich in (iron, sulphur, carbon dioxide and so on) and a small drinking fountain. Locals come down with empty bottles and fill up; some of the waters are pleasantly mineral, some genuinely unpalatable. The park is free, open at all hours, and best visited in the early morning when the temperature contrast makes the steam most visible.