These baths were the part of imperial palace. In Trier there is another bath complex which is even bigger then Imperial Baths but less impressive.
In the Middle Ages the baths were included into the city’s defense system and served as the bastion. Also the baths served as the city’s gate until 19 century.
Entire complex was explored during the several excavations and original structure of the baths is now clearly visible. Baths include several rooms, places for heating and the underground passage which is most interesting part of the complex.