Set inside a stunning ultra-modern building designed by American architect Richard Meier, the temple-like marble “Altar of Peace” was erected in 9 B.C. to honor soon-to-be-Emperor Augustus’s success in subduing tribes north of the Alps. For centuries the monument was lost to memory; signs of its existence surfaced in the 16th century, but it wasn’t until the 1930s that it was fully excavated, and even so it lay virtually abandoned after World War II, until a true restoration began in the 1980s. The exhibit complex provides context, with interactive displays in English. From here you get great views of the huge, overgrown ruin of Augustus’s Mausoleum (Mausoleo di Augusto), built in the 1st-century B.C., where the ashes of emperors Augustus, Caligula, Claudius, Nerva, and Tiberius once rested. Long closed to the public, the tomb is now being restored, with plans to reopen in 2020. Offered most Friday and Saturday evenings and nightly in high season, L’Ara com’era (The Ara as it was) ★★, an immersive virtual reality experience, transports visitors to the Ara and its surroundings during their 1st-century heyday (adults 12€, no children under 13).