The Ponte dei sospiri connects the Doge's Palace with the associated prisons. It is probably one of the most photographed bridges in the world, how you can notice by the hustle on the opposite bridge in the picture.
Here once Casanova sighed his heavy gear in the lead chambers, from where he luckily escaped.
In they went to go to prison, out they came for execution. For many prisoners it was the last open view of the lagoon. Often copied, never equaled: in Oxford at the prestigious St. John College, there is a bridge similar style - they probably passed the test items to last exam?