One of the longest calli (streets) in Castello leads back from the Fondamenta Tetta (canalside walkway) towards Campo Santa Maria Formosa: a street of workshops, bookshops and small courtyards where two worlds coexist – medieval Venice, which left in an inner courtyard one of its oldest vere da pozzo (wellheads), and postcard Venice, with the most photographed bookshop in the city, the Acqua Alta, where the books sit in a gondola to escape the tides.