The Baths of Caracalla were the second largest Roman public baths, or thermae, in Rome. It was built between AD 212 and 217, during the reigns of Septimius Severus and Caracalla. They would have had to install over 2,000t of material every day for six years in order to complete it in this time.
The baths remained in use until the 6th century when the complex was taken by the Ostrogoths during the Gothic War, at which time the hydraulic installations were destroyed. The bath was free and open to the public. The earthquake of 847 destroyed much of the building, along with many other Roman structures.
The building was heated by a hypocaust, a system of burning coal and wood underneath the ground to heat water provided by a dedicated aqueduct. It was in use up to the 19th century. The Aqua Antoniniana aqueduct, a branch of the earlier Aqua Marcia, by Caracalla was specifically built to serve the baths. It was most likely reconstructed by Garbrecht and Manderscheid to its current place.
In the 19th and early 20th century, the design of the baths was used as the inspiration for several modern structures, including St George's Hall in Liverpool and the original Pennsylvania Station in New York City. At the 1960 Summer Olympics, the venue hosted the gymnastics events.
References:The Church of St Donatus name refers to Donatus of Zadar, who began construction on this church in the 9th century and ended it on the northeastern part of the Roman forum. It is the largest Pre-Romanesque building in Croatia.
The beginning of the building of the church was placed to the second half of the 8th century, and it is supposed to have been completed in the 9th century. The Zadar bishop and diplomat Donat (8th and 9th centuries) is credited with the building of the church. He led the representations of the Dalmatian cities to Constantinople and Charles the Great, which is why this church bears slight resemblance to Charlemagne's court chapels, especially the one in Aachen, and also to the Basilica of San Vitale in Ravenna. It belongs to the Pre-Romanesque architectural period.
The circular church, formerly domed, is 27 m high and is characterised by simplicity and technical primitivism.