Castel Sant'Angelo
The Castel Sant'Angelo, initially known as the Mausoleum of Hadrian, was a significant, cylindrical fortress located on the Vatican. An end point to the Passetto di Borgo, the Assassin Ezio Auditore scaled the Castel Sant'Angelo during his infiltration of the Sistine Chapel in 1499.
History
Firstly, the Castel Sant'Angelo was commissioned by the Roman Emperor Hadrian as a tomb for himself and his family. Later, during the Renaissance, the building was used by the popes as a fortress and castle.
The Roman Era
The tomb of Hadrian, also called Hadrian's mole, was constructed on the right bank of the Tiber, between 135 and 139 AD. It was originally a decorated cylinder, with a garden top and golden quadriga. Hadrian's ashes were placed here a year after his death in 138 AD, together with those of his wife, and his first adopted son, who died in the same year. Furtherly, remains of succeeding emperors were placed here as well. Hadrian also built the Ponte Sant'Angelo, formerly known as Pons Aelius.
Destruction
Much of the tomb contents and decoration had been destroyed since the building was changed into a military fortress in 401. The urns and ashes were scattered by looters in Alaric's sacking of Rome in 410, and the original decorations were thrown down upon the attacking Goths when they besieged Rome in 537.
Liberation of Rome
The Castel is the most heavily guarded building in Rome. In 1501, Ezio Auditore infiltrated the Castel to rescue Caterina Sforza, and to assassinate Cesare and Rodrigo Borgia. However, though he successfully rescued Caterina, he was unable to kill either Templar leader, after he discovered that Rodrigo was away from the Castel, and that Cesare had left for Urbino moments after Ezio had arrived.
In August 1503, Ezio once again infiltrated the Castel through a side gate with a key he had obtained from Lucrezia's lover Pietro. At a window along the wall of the fortress, he witnessed the murder of Rodrigo Borgia at the hands of Cesare. Ezio also found out the location of the Apple of Eden, thanks to Lucrezia, after realizing what kind of man her brother was.[1]
Trivia
- Despite being the highest reachable climb point of any Assassin's Creed game, the flagpole atop the Castel is not a view point.
- After climbing the flagpole and looking out at the cityscape, clouds appear over the city.

- The achievement "Fly Like An Eagle" can be earned when Ezio jumps off the pinnacle height of the Castel (the top of the flagpole) with a parachute.
- Throughout Sequence 5, both entrances to the Castel (the large door near the four Papal guards, and the fence accessing the lower courtyard) are closed, so completion of the "Fly Like An Eagle" achievement is not possible until further game progression.
- One of Subject 16's Rifts is located on the Castel, on the main tower just across from the inner wall.
- The entire Castel is a forbidden area throughout Assassin's Creed: Brotherhood, except during certain memories, such as "The Ezio Auditore Affair."