The Porta Maggiore (Veduta del Monumento eretto dall'Imperador Tito Vespasiano per aver ristaurati gl'Aquedotti . .)

The Porta Maggiore stands on a site crucial to the development of Rome, where nine of its eleven aqueducts entered the city. From this site, called "Ancient Hope" in the Republican era, the aqueducts diverged to carry water to all parts of the city. The Porta Maggiore itself was built by the emperor Claudius (AD 41- 54) in 52 as part of two new aqueducts, the Aqua Claudia and the Anio Novus. Two important roads, the Via Praenestina and the Via Labicana, also entered the city through the arches at this point. The rusticated masonry of the piers is typical of Claudian monuments. The water ran in channels in the attic above the rough blocks of stone. The building only became a porta or gate proper in the late third century AD when it was incorporated as part of the city walls constructed by the emperor Aurelian (270-275). In this veduta Piranesi has imagined away the numerous structures that had grown up around the monument over the centuries, but he has not tried to make it look new. Vegetation sprouts from the top, and the gable on the rightmost pier has crumbled. The arches were not actually excavated to the depth shown by Piranesi until 1834.