The Palazzo Contarini del Bovolo is a charming little palace in Venice, famous for its spiral staircase called the Scala Contarini del Bovolo. It was built in the 15th century by the Contarini family, and from this palace you can enjoy one of the best views of the city. You can spot many famous sights like St Mark's Basilica's Dome, the Bell Tower and much more.

The adult ticket is €9 and it can purchased both online and on the spot. I recommend buying them online, so you're sure to get in. As Venice is pretty crowded, it's always recommended to plan this kind of sights in advance.