The Baths of Diocletian

Map

Baths of Diocletian

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The Thermae Diocletiani (Baths of Diocletian), which were built between 299 and 308, were the largest of the ancient Roman world. The entire complex, which also included gardens and galleries, measured 376 by 361 metres (33 acres). 

The main entrance to the baths was to the northeast. To the southwest was a large exedra, which is still visible as the outline of Piazza della Repubblica. The exedra was flanked by two large buildings, most likely libraries. These in turn connected to circular halls, one of which is now the church of San Bernardo. 

The central block of the baths, which measured 280 by 160 meters (910 by 520 feet), consisted of the frigidarium, tepidarium and caldarium, with other halls arranged symmetrically around them. Flanking the frigidarium were two open-air gymnasia. 

The Baths of Diocletian remained in use until the siege of Rome, in 537, when the Ostrogoths cut off the aqueducts.

In 1561 Pope Pius IV (r. 1559-65) commissioned Michelangelo to convert part of the baths into the church of Santa Maria degli Angeli e dei Martiri.  And in 1575 Pope Gregory XIII (r. 1572-85) began turning several of the surviving halls into warehouses for the storage of grain and oil.  

Since 1889 the Baths of Diocletian have housed the Museo Nazionale Romano, the national collection of ancient Roman art.    

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1: Caldarium 2: Tepidarium 3: Frigidarium 4: Natatio 5: Gymnasia 6: Entrance 7: Exedra