The amazing preservation of one of the most unique features of Roman Britain.
Interesting displays where you can see some of the original foundations, hypercausts etc.
As well as the holy spring, where the hot springs flow out and of course the great Roman bath itself.
The Roman architecture as well as the Roman sculptures on the walkway above the Roman bathing pools are simply stunning.
Don't forget to get the audio guide given at the gate, there is a lot of information at every step.