The water we see in the Baths today fell as rain on the Mendip Hills many hundreds or even thousands of years ago.  It percolates deep down through limestone aquifers, heated by the earth's core and raising the temperature to between 64 -96 degrees.  Under pressure the heated water rises to the surface at 46 degrees along fissures and faults through the limestone beneath Bath.

By the first century AD this part of Britain was occupied by an Iron Age tribe called the Dobunni.  They believed that the hot spring was sacred to the Goddess Sulis who was thought to possess curative powers.  In AD43 the Roman armies invaded Britain and by AD75 they had built a new religious spa complex around the thermal spring and the settlement then grew as a centre for health and pilgrimage. It was named Aquae Sulis meaning ‘the waters of Sulis’.  To keep good relations with local people the Romans were sensitive to their gods and goddesses and the goddess worshipped at the temple here was known as Sulis Minerva combining Celtic and Roman elements.

The Romans built the baths using the 1.3 million litres of naturally-heated water that rose to the surface naturally each day. The baths combined healing with leisure and water was channelled through the baths using lead pipes and lead lined channels. Even the baths were lined with lead. People came from far and wide to bathe in the waters and worship at the temple.

In the fourth century, barbarian raids from Northern Europe and Ireland and political instability in the Roman Empire made trade and travel increasingly difficult.  The number of visitors to Aquae Sulis declined, and at the same time flooding from the River Avon resulting from poor maintenance meant black mud began to cover everything.  The Temple buildings collapsed and the roofs of the baths eventually crashed into the growing swamp.

By the twelfth century the King’s Bath, formed within the shell of the Roman reservoir chamber, was enclosed within the precincts of the post- Roman monastery.  Medical practice promoted bathing in the thermal waters to cure ailments as belief in its power re-emerged in the legend of the prehistoric Prince Bladud:  in the ninth century BC, it was said Bladud contracted leprosy but was cured by the thermal waters of Bath.

In the late seventeenth century doctors began recommending drinking the water as a remedy for internal conditions and the first Pump Room, opened in 1706, placed drinking prescribed quantities of the water at the heart of the emerging spa culture. 

In 1878, the city surveyor architect Major Charles Davis, worried by a leak from the King's Bath spring, decided to explore the ground around it.  In doing so he found Roman remains and by 1880 had uncovered large parts of the Great Bath. The site was opened to visitors in 1897 and throughout the 20th century was progressively extended, notably with the east baths in the 1920s and later when the Temple Precinct was excavated beneath the Pump Room in 1981-83. A new learning centre will be opened up for the public in an area of Roman remains to the south of the site, where several underground vaults and tunnels lead into some currently inaccessible remains from the Roman bath house and town.

The practice of drinking the thermal waters of Bath only began in earnest in the later seventeenth century. It became necessary to install a pump to allow patients to have access to the water directly from the spring and in the first years of the eighteenth century a doctor, William Oliver, persuaded the Bath Corporation to erect a building where the drinkers could be sheltered.  This is the origin of the first Pump Room completed in 1706.   As the popularity of the spa grew in the 18th century the Pump Room could no longer accommodate the fashionable crowds and invalids so extensions and improvements were made to the building. 

In the later eighteenth century, as more and more families came to Bath to take the waters, the Pump Room needed further work. In 1784 a lavatory was installed but then An Act of Parliament was obtained establishing Improvement Commissioners to improve the city centre and the architect, Thomas Baldwin, was appointed by them. Baldwin built New Private Baths adjacent to the Pump Room and in 1790 began work to build an entirely new one. Despite delays arising from Baldwin’s personal bankruptcy and dismissal, the project was completed by a new architect, John Palmer, in 1795 when it was opened by the Duchess of York. The wider scheme re-ordered the local streets, sweeping away medieval alleys and before his dismissal Baldwin completed Bath Street connecting the Pump Room to the two smaller springs known as the Hot Bath and the Cross Bath. 

The Pump Room continued as a fashionable meeting place to promenade and take the waters.  Jane Austen observed people and fashions from within the Pump Room, which features in her two novels ‘Northanger Abbey’ and ‘Persuasion’.

In 1897 John Brydon built another extension to the Pump Room which housed a Concert Hall, the present day Roman Baths Reception Hall, undoubtedly the finest Victorian interior in Bath.  Mary Shelley stayed at 5 Abbey Church Yard which was demolished to make room for the Reception Hall and it is thought that this is where her novel Frankenstein was written.

During the Victorian and Edwardian periods, the Pump Room was heavily furnished and during World War II it became a restaurant and fortunately escaped damage in the Baedeker air raids on Bath in 1942. Many interesting historical figures have visited the Pump Room and taken the waters including Jane Austen, Charles Dickens, Buffalo Bill and Haile Selassie, not to mention present day royalty and celebrities.

Today, the Pump Room is a very popular venue for day time refreshments, and is also used for special occasions, corporate hospitality, concerts, weddings and as a favourite rendezvous for both local people and visitors to the city.