Palazzo Contarini del Bovolo is a late Gothic palace in Venice famous for its extraordinary external spiral staircase, the Scala del Bovolo ("bovolo" means snail shell in Venetian dialect). Tucked into a quiet courtyard between Rialto and Piazza San Marco, it is one of Venice's most surprising architectural discoveries. The oldest section of the palace dates to the 1300s, when the Contarini family of the San Paternian branch chose this location for its strategic position, roughly equidistant from the commercial hub of Rialto and the political center of San Marco. The palace functioned as a "fontego" house, a merchant's combined residence and warehouse, reflecting the practical architecture of Venetian aristocratic life before display became paramount. The facade once bore elaborate floral frescoes, fragments of which survive today. In 1499, Pietro Contarini commissioned the famous spiral staircase to enhance the palace's courtyard elevation. The building changed hands many times over the centuries. In the 19th century, a lodging-house keeper named Arnaux Marseille, nicknamed "il Maltese," ran the palace as a boarding house. Local legend holds that he inspired Hugo Pratt's comic character Corto Maltese. One of his guests, the German astronomer Wilhelm Tempel, discovered the C/1859 comet and the Merope Nebula of the Pleiades while observing the sky from the building's upper terrace. The palace is now owned by I.P.A.V. (Public Institutions of Venetian Assistance) and serves as their headquarters, with the staircase and exhibition rooms open to visitors.