License, verbatimCC0
The Metropolitan Museum of Art: Open Access, Creative Commons Zero (CC0). Flagged isPublicDomain=true in the museum's own record.
Francesco Piranesi. Large plan of the entrance of the town of Pompeii, and its surrounding buildings, from "Antiquités de Pompeïa, tome premier, Antiquités de la Grande Grèce..." (Antiquities of Pompeii, volume one, Antiquities of Great Greece...), volume 1, plate 2, 1804. The Metropolitan Museum of Art.