The museum takes its name from two popes: Clement XIV, who established the museum, and Pius VI, who brought it to completion. Clement XIV came up with the idea of creating a new museum in Innocent VIII's Belvedere Palace and started the refurbishment work.

Clement XIV founded the Museo Pio-Clementino in 1771; it originally contained artworks of antiquity and the Renaissance. The museum and collection were enlarged by Clement's successor Pius VI. Today, the museum houses works of Greek and Roman sculpture. Some notable galleries are as follows:

Octagonal Court (aka Belvedere Courtyard and Cortile delle Statue)

This was where some of the first ancient classical statues in the papal collections were first displayed. Some of the most famous pieces, the Apollo of the Belvedere and Laocoön and His Sons have been here since the early 1500s.

Sala Rotonda

This houses the statue group of Apollo and the nine muses, uncovered in a Roman villa near Tivoli in 1774, as well as statues by important ancient Greek or Roman sculptors. The centerpiece is the Belvedere Torso, revered by Michelangelo and other Renaissance men.

Sala degli Animali

so named because of the many ancient statues of animals

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