Public baths were one of the central institutions of Roman life. Romans visited the baths in the early afternoon before going home for the main meal of the day (cena). Men met at the baths to relax, to socialise and to talk business, as well as to get clean and keep fit. Women usually bathed separately. Sometimes they had their own baths with a separate entrance. The remains of many bath-houses have been found in Roman Britain.

A bath-house included an exercise hall and changing rooms, and three main chambers: a cold room (frigidarium), a warm room (tepidarium) and a hot room (caldarium). Bathers advanced from the cold room to the hot room and finished off with a plunge into a cold bath or swimming pool. Roman building and plumbing technology made the construction of bath-houses possible. In addition to a good water supply, an efficient method of heating was needed. This was achieved through a hypocaust: the floors were raised on brick pillars, which allowed heat from a furnace to circulate underneath.

Bathing was considered essential in the Roman army. One of the largest of many bath-houses found in military forts was built on the site of modern Exeter. It was the only stone building constructed during the occupation of the IInd Augusta Legion in the 60s AD.