Valley of the Colosseum and Caelian Hill. View from the eastern Palatine Hill.

The Caelian Hill (Latin: Collis Caelius; Italian: Celio) is one of the famous Seven Hills of Rome. Under reign of Tullus Hostilius, the entire population of Alba Longa was forcibly resettled on the Caelian Hill. According to a tradition recounted by Titus Livy, the hill received its name from Caelius Vibenna, either because he established a settlement there or because his friend Servius Tullius wished to honor him after his death.
In Republican-era Rome the Caelian Hill was a fashionable residential district and the site of residences of the wealthy. Archeological work under the Baths of Caracalla have uncovered the remains of lavish villas complete with murals and mosaics. The Caelian is also the site of the Basilica of Santi Giovanni e Paolo and the ancient basilica of Santo Stefano Rotondo, known for its centralized, circular plan. A significant area of the hill is taken up by the villa and gardens of Villa Celimontana.

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