The Imperial Palace incorporated the earlier republican villa. It was entered from stairways (1, 2) off the Library Courtyard. The rooms were disposed along the sides of five courts or peristyles (5, 6, 24, 35, 54, and the unnumbered spaces abutting rooms 9, 11, 13, and 16). Off the entrance peristyle (5, 6) were four rooms dedicated to imperial business (29-32). These rooms were lavishly decorated in opus sectile; the floor of 19 ("Triclinium of the Centaurs") included the polychrome mosaics in opus vermiculatum in the Vatican and Berlin museums. Room 31 is interpreted as a library. Off the peristyle beyond to the south were offices for staff (39-48). South of the peristyle was the Nymphaeum (54); in the southwest corner was a summer triclinium (61). On the northwest side of the complex were the emperor's private suite of rooms, including his bedroom (8) and private latrines (10, 12). The modifications to the republican villa date to Phase I (118-125).