The Mausoleum of Hadrian, today's Castel Sant'Angelo, was the new imperial dynastic tomb of Emperor Hadrian, whose construction began in 123 AD.
Until then the emperors and their families had been buried in the Mausoleum of Augustus, which he had built when he was still alive in the Campus Martius, a place of great symbolic significance, where the funerals and triumphs of the most important Roman figures had taken place.
In this way he had given his Mausoleum much greater visibility than it would have had if he had chosen the Via Appia, where prestigious Mausoleums such as that of Caecilia Metella already stood.
At the beginning of the 2nd century. A.D. there was no longer room in the Mausoleum of Augustus. The last emperor to be buried there was Nerva, while an exception was made for Trajan, allowing the urn with his ashes to be placed in the base of Trajan's Column, within the city walls.
Hadrian decided to build his Mausoleum in the same area of the Campus Martius, to ideally recall Augustus as the re-founder of the greatness of Rome; like him he had put an end to wars and built or restored temples and public buildings, renewing the splendor of Rome.
Hadrian also wanted to give maximum visibility to his Mausoleum: in fact also today it can be seen from almost the entire city and is one of its iconic monuments, together with the Altare della Patria and the dome of St. Peter.
Since in the Campus Martius between ustrina (funerary altars), monuments and temples dedicated to the deceased and deified emperors there was not enough space for a building of that size, Hadrian chose a very nearby area, on the right bank of the Tiber: the Horti Domitiae, which had long been part of the imperial properties.
In this way the two Mausoleums found themselves close both physically and ideally: the monumental Aelius Bridge was also a symbolic bridge between the two buildings and the two emperors.
A monumental tomb and a magnificent palace were two sides of the same coin: propaganda and legitimation of imperial power.
On the Palatine, which since the Republican era was the "exclusive" quarter of the aristocrats, the houses of Livia and Augustus still exist.
Their successors, starting with Tiberius, built the imperial palace there, which over the centuries was expanded and modified several times. Hadrian, who did not love Rome, instead of enlarging the Palatine palaces, had Hadrian's Villa built in Tivoli.
If the Palatine palace was sumptuous, the imperial tomb could not be less: both buildings were the quintessence of the iconography of power. The large size, the elevated position and the luxurious decoration were a non-negligible aspect of the propaganda: they showed that the rulers were a step higher than ordinary mortals and the plebs.
As we explain in our book «Castel Sant'Angelo. Mausoleum of Hadrian. Architecture & Light" (also in English edition), the great Mausoleums had a very precise symbolic meaning, linked to the cult of the dead in general and above all to the cult of the ancestors, who in the case of the Roman emperors were deified, and gave a sacred connotation to the power of the dynasty.
While he was alive, Hadrian had been divi filius, that is, son of the deified emperor Trajan. Therefore he was semi-divine, and intermediary between men and gods, with the very important task of maintaining the Pax Deorum (peace of the gods), the divine favor towards the Roman State, the Princeps and his entire family.
The same had previously happened to Augustus: he too had been divi filius, (adoptive) son of the deified Julius Caesar. This will happen for subsequent emperors, even for those who had the damnatio memoriae for their misdeeds such as Nero or Caracalla or Elagabalus.
The Mausoleum of Hadrian was therefore a true ideological manifesto of the power and wealth of the new dynasty, of which Hadrian became the tutelary deity, depicted as Sol Invictus driving the Quadriga of the Sun that crowned the Temple at the top of the Mausoleum, holding in his hands the reins of the Universe.
The book «Mausoleum of Hadrian. Architecture & Light» explains in detail the secret symbolic meaning of the building, linked to ancient sacred elements such as the Etruscan Templum and the Axis Mundi.
Thanks to the discoveries of Archaeoastronomy and the illuminations at the Summer Solstice which are widely talked about, we have proposed a new and unprecedented reconstruction of the building including the location of burials of the other members of the imperial family.