Built by Hadrian (117-138) on pre-existing baths and then restored at the end of the 2nd and the fourth centuries CE
Frigidarium with two granite columns and other marine mosaics
Room with mosaics depicting boxers
Hypocausts or heating systems underneath the floor of the baths
Basement fires heated the air which flowed between the columns of stone or tile, which supported the floor. Note below the rows of tile pipes in the walls which conveyed hot air to the rooms as well.