This architectural gem is hidden in a small courtyard at the back of the Palazzo Contarini Minelli dal Bovolo in Venice. Built in 1499, the spiral staircase owes its name to the Venetian word ‘bovolo’, or snail shell. The architecture is a mixture of early Venetian Renaissance and Gothic-Byzantine building techniques, with its main feature the arches and railing that follow the winding staircase to the top of the building. In this photograph, the loggias – galleries that are opened up to one side by a series of arches – have been closed off with walls and windows. This indicates that in the 1850s these narrow balconies were used as rather rundown living spaces. Today, the loggias have been returned to their original state and the 121 stairs can be climbed by visitors.