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. The Piazza Navona, Rome, above the ruins of the Circus of Domitian, the Church of Sant Agnese to the right, Bernini's fountain in the center, from "Vedute di Roma", 1760–78. The Metropolitan Museum of Art.