The hot springs that have given Bath its name have been rushing to the surface at a constant temperature of 50°C since time immemorial. They were certainly known to the Celts but it was only with the arrival of the Romans that the spas grew in fame and prosperity, attracting high ranking officers in the Roman army from all over Europe.
The town was firmly established in the first two decades of the Roman invasion of AD 43 and it was the Romans who gave the name to the original town: Aquae Sulis and it was they who built the temple which incorporated in its name ("Sul Minerva") the religious beliefs of Romans and Celts alike. One important archaeological find was the head of Sul, the Celtic sun god.
Around this health resort the Romans built a temple and a forum and the city began to expand around these focal points and was later circumscribed by the building of the town walls.
When the Roman Empire began to collapse and the Roman armies left England, as in the rest of the country, what they had constructed in Bath also fell into decay. The Saxons were, of course, aware of the existence and importance of the town but their limited knowledge and expertise meant that the springs were neglected. They gradually became covered in alluvial mud and hidden from sight for over a thousand years to be rediscovered only towards the end of the 19th century. The town, however, continued to develop: in around 760 King Offa founded an Abbey dedicated to St Peter and in which Edgar was crowned king. This event alone is sufficient proof of the enormous importance of Bath at that time.