Housing the extraordinary Altar of Augustan Peace, the Ara Pacis Museum is located by the Tiber and the nearby Mausoleum of Augustus. Google Map Link. Originally constructed along the ancient Via Flaminia, now the Corso, (Google Map Link) the Ara Pacis was erected in honor of Emperor Augustus’s victories in Gaul and Spain and was dedicated on January 30, 9 B.C.E. A U-shaped altar with beautiful carved marble, the Ara Pacis is the centerpiece of the museum designed by architect Richard Meir, replacing an earlier museum commissioned by Mussolini in 1938. In addition to showcasing the altar, the museum serves as exhibition space for many different kinds of shows running the gamut from antique sculpture to modern fashion. Currently, it is displaying works of Toulouse-Lautrec from Budapest. The official museum site notes hours, history and current exhibits. For more details concerning the altar, see A Walk Through The Field of Mars (Walk Three, Nos. 9 and 14)