The Castel Sant'Angelo, initially known as the Mausoleum of Hadrian, is a cylindrical fortress located in the Vaticano District, reachable via the Ponte Sant'Angelo. It is an end point to the Passetto di Borgo, and is found on the banks of the Tiber river.
The tomb of Hadrian, also called Hadrian's mole, was constructed between 135 and 139. 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, together with those of his wife, and his first adopted son, who died in the same year. Furthermore, remains of succeeding emperors were placed here as well. Hadrian also built the Ponte Sant'Angelo, formerly known as Pons Aelius.
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
In 1501, upon Ezio's return to Rome, he infiltrated the Castel Sant'Angelo to rescue Caterina Sforza, and to assassinate Cesare and Rodrigo Borgia. However, though he successfully rescued Caterina, he was unable to kill either of the Templars, after he discovered that Rodrigo was away from the castle, and that Cesare had left for Urbino moments after Ezio had arrived.
In August 1503, Ezio once again infiltrated the Castel Sant'Angelo through a side gate, with a key he had obtained from Lucrezia Borgia's lover, Pietro Rossi. At a window looking into the castle's Papal apartments, he witnessed the murder of Rodrigo at the hands of Cesare. At this time, Ezio also found out the location of the Apple of Eden from Lucrezia.
- Despite being the highest reachable point of any Assassin's Creed game, the flagpole atop the castle was not a view point.
- After climbing the flagpole and looking out at the cityscape, clouds appeared below the pole itself.
- One of Clay Kaczmarek's rifts was located on the castle, on the main tower just across from the inner wall.
- The entire castle was a restricted area throughout Assassin's Creed: Brotherhood, except during certain memories, such as "The Ezio Auditore Affair."
- The achievement "Fly Like An Eagle" could be earned once Ezio jumped from the pinnacle of the castle with a parachute.
- Throughout Sequence 5, it was impossible to access the castle; as a result, the "Fly Like An Eagle" achievement could not be achieved until further game progression.