Il Ponte dei Sospiri
The world's most poetically-named bridge, Il Ponte dei Sospiri (the Bridge of Sighs), was built in 1614 so that prisoners of the Venetian state could be transferred in secret from the Doges' Palace to the Nuovi Prigioni (New Prisons). The wistful name was actually conceived by English poet Lord Byron in the early 1800s as he imagined the horror of prisoners taking their last glimpse of Venice before going underground to captivity.
Although Venice in the 1600s was a famously permissive society, it was overseen by a shadowy oligarchy through an omnipresent secret police that sniffed out any hint of political treachery against the all-powerful Republic. The slightest suspicion could lead to a midnight arrest and secret trial; prisoners would be tortured and convicted without being told the charge—or the length of their sentence. The cells for new prisoners were located around the torture room so they could hear the victims' screams, designed to wear them down psychologically in advance.
Today, the New Prison is part of the standard Doges' Palace tour. One can follow the route of the prisoners across the covered bridge, which was divided for 2-way traffic, and peer through the grill to the sparkling Lagoon as gondolas pass underneath. Visitors should also keep an eye out for the more recent graffiti—the cells were still in use for political prisoners in the 1930s for victims of Mussolini's fascist regime.