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. View of the arches of the consuls Dolabella and Silanus enclosed within the Neronian arches of the Acqua Claudia, from "Roman Antiquities" (Le Antichità Romane), 1756. The Metropolitan Museum of Art.