License, verbatimCC0
The Metropolitan Museum of Art: Open Access, Creative Commons Zero (CC0). Flagged isPublicDomain=true in the museum's own record.
Giovanni Battista Piranesi. Plate 19: Part of the ancient Appian Way about three miles outside Porta S. Sebastiano, from "Alcune Vedute di Archi Trionfali ed altri monumenti inalzati da Romani parte de quali se veggono in Roma e parte per l'Italia" (Some Views of Triumphal Arches and other monuments erected by the Romans, some of which are in Rome and some elsewhere in Italy), ca. 1748. The Metropolitan Museum of Art.