Between 1802 and 1806 Valadier turned the main building into a palace, and transformed other buildings. He also laid out the park with symmetrical avenues around the palace. Numerous works of classical art, many of which were sculptures, were purchased to furnish the palace. Following the death of Giovanni, Alessandro commissioned the painter and architect Giovan Battisti Caretti in 1832 to further develop the property. In addition to expanding the buildings, Caretti constructed several buildings in the park. These included the False Ruins, the Temple of Saturn, and the
Tribuna con Fontana. To plan and carry out other works, Alessandro employed Quintiliano Raimondi for the theatre and orangerie (today known as the "Lemon-house"), and
Giuseppe Jappelli, who was in charge of the entire south section of the grounds, which he transformed with avenues, small lakes, exotic plants and unusual buildings. These included the Swiss Hut (later rebuilt as the
Casina delle Civette), the
Conservatory, the Tower and
Moorish Grotto, and the Tournament Field. The project culminated in 1842 with the erection of two pink granite obelisks that commemorated Alessandro's parents. In 1919 a large underground 3rd- and 4th-century
Jewish catacomb was discovered in the north-west area of the grounds. There are about 3,800 graves in the cemetery. In June 1944 the property was all occupied by the Allied High Command, which remained there until 1947. The Villa was bought by the Municipality of Rome in 1977 and a year later it was opened to the public, but with many of the buildings in a run-down state. Restoration was initiated in the 1990s, and has been largely completed with the exception of the Moorish Conservatory (
Serra Moresca), although there is an ongoing restoration of the villa. The landscaped grounds are in the English '
picturesque' style. ==The museum==