Capitoline Museums (Musei Capitolini) are a group of art and archeological museums in Piazza del Campidoglio, on top of the Capitoline Hill in Rome, Italy. The museums are contained in three palazzi surrounding a central trapezoidal piazza in a plan conceived by Michelangelo Buonarroti in 1536 and executed over a period of over 400 years. The history of the museums can be traced to 1471, when Pope Sixtus IV donated a collection of important ancient bronzes to the people of Rome and located them on Capitoline Hill. Since then, the museums' collection has grown to include a large number of ancient Roman statues, inscriptions, and other artifacts; a collection of medieval and Renaissance art; and collections of jewels, coins, and other items. The museums are owned and operated by the municipality of Rome.The statue of a mounted rider in the centre of the piazza is of Emperor Marcus Aurelius. It is a copy, the original being housed on-site in the Capitoline museum. Many Roman statues were destroyed on the orders of Christian Church authorities in the Middle Ages; this statue was preserved in the erroneous belief that it depicted the Emperor Constantine, who made Christianity the official state religion of the Roman empire.
The Capitoline Museums Rome are composed of three main buildings surrounding the Piazza del Campidoglio and interlinked by an underground gallery beneath the piazza.
The three main buildings of the Capitoline Museums are:
* Palazzo Senatorio, built in the 12th century and modified according to Michelangelo's designs;
* Palazzo dei Conservatori, built in the mid-16th century and redesigned by Michelangelo with the first use of the giant order column design; and
* Palazzo Nuovo, built in the 17th century with an identical exterior design to the Palazzo dei Conservatori, which it faces across the palazzo.
In addition, the 16th century Palazzo Caffarelli-Clementino, located off the piazza adjacent to the Palazzo dei Conservatori, was added to the museum complex in the early 20th century.