Housed in the twin palaces of Palazzo Nuovo and Palazzo dei Conservatori, standing on opposite sides of Michelangelo’s piazza del Campidoglio, the Capitoline Museums constitute the oldest public gallery in the world. Their collection was begun in 1471, when Pope Sixtus IV presented the Roman people with a group of classical sculptures. Sixtus’s successors continued to enrich the collection with examples of ancient art (mostly sculptures) and, at a later date, some important Renaissance and post-Renaissance paintings. The entire collection was finally opened to the public in 1734, by Pope Clement XII. Many statues remain frustratingly labelless but there is a decent audioguide. Part of the ancient sculpture collection from the Musei Capitolini can be seen at the Centrale Montemartini too.