The Roman Baths complex is a site of historical interest in the English city of Bath. The house is a well-preserved Roman site for public bathing.
The Roman Baths themselves are below the modern street level. There are four main features: the Sacred Spring, the Roman Temple, the Roman Bath House and the Museum holding finds from Roman Bath. The buildings above street level date from the 19th century.
The water which bubbles up from the ground at Bath falls as rain on the nearby Mendip Hills. It percolates down through limestone aquifers to a depth of between 2,700 and 4,300 metres (8,900 and 14,100 ft) where geothermal energy raises the water temperature to between 69 and 96 °C (156.2 and 204.8 °F). Under pressure, the heated water rises to the surface along fissures and faults in the limestone. This process is similar to an artificial one known as Enhanced Geothermal System which also makes use of the high pressures and temperatures below the Earth’s crust. Hot water at a temperature of 46 °C (114.8 °F) rises here at the rate of 1,170,000 litres (257,364 imp gal) every day,from a geological fault (the Pennyquick fault).
The first shrine at the site of the hot springs was built by Celts, and was dedicated to the goddess Sulis, whom the Romans identified with Minerva. Geoffrey of Monmouth in his largely fictional Historia Regum Britanniae describes how in 836 BC the spring was discovered by the British king Bladud who built the first Moorish baths. Early in the 18th century Geoffrey’s obscure legend was given great prominence as a royal endorsement of the waters’ qualities, with the embellishment that the spring had cured Bladud and his herd of pigs of leprosy through wallowing in the warm mud.
The name Sulis continued to be used after the Roman invasion, leading to the town’s Roman name of Aquae Sulis (“the waters of Sulis”). The temple was constructed in 60-70 AD and the bathing complex was gradually built up over the next 300 years. During the Roman occupation of Britain, and possibly on the instructions of Emperor Claudius, engineers drove oak piles to provide a stable foundation into the mud and surrounded the spring with an irregular stone chamber lined with lead. In the 2nd century it was enclosed within a wooden barrel-vaulted building, and included the caldarium (hot bath), tepidarium (warm bath), and frigidarium (cold bath). After the Roman withdrawal from Britain in the first decade of the 5th century, these fell into disrepair and were eventually lost due to silting up, and flooding. The Anglo-Saxon Chronicle suggests the original Roman baths were destroyed in the 6th century.
About 130 curse tablets have been found. Many of the curses related to thefts of clothes whilst the victim was bathing.
The museum houses artefacts from the Roman period including objects which were thrown into the Sacred Spring, presumably as offerings to the goddess. These include more than 12,000 Roman currency coins which is the largest collective votive deposit known from Britain. A gilt bronze head of the goddess Sulis Minerva, which was discovered nearby in 1727, is displayed.