Originally was built as a Mausoleum for Emperor Hadrian.
Situated on the right of the River Tiber, Castel Sant’ Angelo was first a mausoleum and after was a fortress as Papal Residence and finally as a barracks and military prison. The building consisted of a square base of 89 metres and a cylindrical colonnaded of 64 metres of diameter. The bridge in front of Castel Sant’Angelo is “Ponte Sant’Angelo” and Its many statues were added in the baroque period.