CASTEL SANT’ANGELO: MAUSOLEUM AND IMPREGNABLE FORTRESS
Hadrian's Mausoleum had the shape of a large circular Tower and since the 5th century AD it was transformed into a fortress. This also happened with other Mausoleums such as that of Cecilia Metella on the Appian Way, which was included in the fortification called Castrum Caetani.
The Mausoleum took the name of Castel Sant'Angelo only in 590 AD after the legendary apparition of the Archangel Michael.
The Aurelian walls were built starting from 270 AD to protect the city of Rome and defend it from increasingly frequent and threatening barbarian attacks. Initially the Mausoleum/Castle was left outside the defensive walls, because it was located on the other bank of the Tiber.
In 401 AD the emperors Honorius and Arcadius strengthened the Aurelian walls by raising them and included the Mausoleum, because it was a strategic observation point, making it the most important defensive stronghold of the city on the right bank of the Tiber.
In 410 and in 455 AD. the Castle resisted the sieges of the Visigoths and the Vandals, who failed to conquer it but sacked the whole city.
In 537 AD Rome was again attacked by the Goths of Vitige and the Romans barricaded themselves inside the Mausoleum under the leadership of General Belisarius.
The Goths launched the assault with a huge number of ladders and ropes. General Belisarius realized that it was not possible to use the Ballistae, i.e. the crossbow-like siege machines created by the Greeks and perfected by the Romans: they could only throw the bolts or projectiles in front, and not from top to bottom, so they were useless.
Map of the Roman Empire at the time of Justinian
Procopius of Caesarea, who describes the siege in his De Bello Gotico written in 550 AD, few years later, said that the Romans, seeing themselves lost, decided to tear into pieces the very large ancient statues that decorated the Mausoleum; they used the marble fragments as projectiles, throwing them at the enemies, who fled.From that moment on, the Mausoleum was plundered of all its precious marbles: for example, the travertine was used to pave the squares of Rome. In the Antiquarium of the Castel Sant'Angelo Museum only a few magnificent fragments are on display, which give an idea of the magnificence of the sculptural decoration.
At the end of the 15th century, when Pope Alexander VI Borgia had new ditches dug around Castel Sant'Angelo, fragments of sculptures were found which confirm the veracity of the story of Procopius. Other fragments were found at the end of the 19h century, during the construction of the ne embankments of the Lungotevere.
This and much more is explained in detail in our book «Castel Sant’Angelo. Mausoleo di Adriano. Architettura e Luce», which traces its two-thousand-year history, closely linked to that of the city of Rome.