Caldarium
(重定向自Calidarium)
A caldarium (also called a calidarium, cella caldaria or cella coctilium) was a room with a hot plunge bath, used in a Roman bath complex.
This was a very hot and steamy room heated by a hypocaust, an underfloor heating system. This was the hottest room in the regular sequence of bathing rooms; after the caldarium, bathers would progress back through the tepidarium to the frigidarium.