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 so-called Temple of Bacchus, now the Church of S. Urban, interior (Veduta interna dell antico Tempio di Bacco, or. di S. Urbano), ca. 1767. The Metropolitan Museum of Art.