The baths of Caracalla (also known as the Antoninian Baths) are the best preserved example of a public bathing complex in Rome. They were begun at the very start of Caracalla's reign in 211 or 212 AD, and the main complex was certainly completed during his reign. It is suggested and very possible that the baths were not completed until the time of Severus Alexander, with the outer complex being added last. There is evidence for repair or alterations during the reigns of Aurelian, Constans and Valentinian and even down into the 6th century under Theodoric, though their function is likely to have changed by then as the aqueduct supplying them was destroyed in 537 AD. A great number of important works of art have been found here, including the famous Farnese Bull that now stands in the museum in Naples. Based heavily on the example of the baths of Trajan on the Oppian, these baths consisted of a central complex, surrounded by gardens, all enclosed by a perimeter wall filled with shops, libraries, nymphaea and the like. The southern side contained the massive cisterns, with stepped seats down from them to a running track. In all, the complex was much more than a bath house and bore more resemblance to a modern leisure centre. The main complex had two floors, both exquisitely decorated and mosaic is still in situ on the ground floor, along with fragments of mosaics that have fallen from higher up. There is an extensive network of subterranean passages and rooms on two levels, though these are not open to the public.