while travelling from Edessa to begin a war with Parthia, he was assassinated while urinating at a roadside near Harran on April 8, 217 by Julius Martialis, an officer in the imperial bodyguard. Herodian says that Martialis' brother had been executed a few days earlier by Caracalla on an unproven charge; Cassius Dio, on the other hand, says that Martialis was resentful at not being promoted to the rank of centurion. The escort of the emperor gave him privacy to relieve himself, and Martialis ran forward and killed Caracalla with a single sword stroke. He immediately fled on horseback, but was killed by a bodyguard archer. Caracalla was succeeded by the Praetorian Prefect of the Guard, Macrinus who almost certainly was part of the conspiracy against the emperor.
The Baths of Caracalla were Roman public baths, or thermae, built in Rome between 212 and 216 AD, during the reign of the Emperor Caracalla. The extensive ruins of the baths have become a popular tourist attraction.
The bath complex covered approximately 13 hectares (33 ac). The bath building was 228 meters (750 ft) long, 116 meters (380 ft) wide and 38.5 meters (125 ft) estimated height, and could hold an estimated 1,600 bathers.
The Caracalla bath complex of buildings was more a leisure centre than just a series of baths. The "baths" were the second to have a public library within the complex. Like other public libraries in Rome, there were two separate and equal sized rooms or buildings; one for Greek language texts and one for Latin language texts.
The baths consisted of a central 55.7 by 24 meter (183x79 ft) frigidarium (cold room) under three 32.9 meter (108 ft) high groin vaults, a double pool tepidarium (medium), and a 35 meter (115 ft) diameter caldarium (hot room), as well as two palaestras (gyms where wrestling and boxing was practiced). The north end of the bath building contained a natatio or swimming pool. The natatio was roofless with bronze mirrors mounted overhead to direct sunlight into the pool area. The entire bath building was on a 6 meter (20 ft) high raised platform to allow for storage and furnaces under the building.
The libraries were located in exedrae on the east and west sides of the bath complex. The entire north wall of the complex was devoted to shops. The reservoirs on the south wall of the complex were fed with water from the Marcian Aqueduct.
Reconstruction of the floorplan of the bath complex.The building was heated by a hypocaust, a system of burning coal underneath the ground to heat water provided by a dedicated aqueduct. It was in use up to the 19th century.
In the early 20th century, the design of the baths was used as the inspiration for several modern structures, including Pennsylvania Station in New York City and National Assembly Building in Dhaka, Bangladesh.
A section of the complex mosaic floor tiling found in the baths.The baths are open to the public on payment of a small charge, which does not apply to students or pensioners. Access is limited to certain areas to avoid damage to the mosaic floors, although such damage is already clearly visible.