It is one of the 12 Tuscolan Villas and is located in Monte Porzio Catone. Built in the 16th century by Cardinal Marco Sittico Altemps on the remains of a pre-existing Roman villa, it was later enlarged and enriched by Popes Gregory XIII, Clement VIII, Paul V and Urban VIII, who made it their summer residence. Its name comes from the dragon symbol, the noble coat of arms of the Boncompagni family, which recurs in many decorations. The villa conceals large rooms inside, many of them richly decorated; among them, the Hall of the Swiss is known for hosting the famous historical event of the Julian Calendar Reformation. Its gardens include a scenic nymphaeum, called the Teatro delle Acque, built at the behest of Cardinal Scipione Borghese. In 1866 the villa was purchased by the Society of Jesus, which gave it to the University of Rome “Tor Vergata” in 1981.