Hadrian had it built as a mausoleum for himself and his family. In order to have an easy access to this sepulchre from the area of Campo Marzio a bridge was built crossing the Tiber river, the Elio Bridge, which was inaugurated in 134 A.D. The construction of the mausoleum was completed after the death of Hadrian (138 A. D.), in 139 A. D., by Antoninus Pius: immediately after his death Hadrian was buried in another place at Pozzuoli (near Naples).
The edifice had a base in brick with a side of 89 mt and 15 mt high, which supported the tomb, a circular structure 64mt in diameter and 21mt high. The exterior was completely covered by veneer marble. Today’s entrance which substitutes the original one is about 3mt higher.
From there a square room (vestibulum) with a niche which contained the huge statue of Hadrian. To the right of this room begins a shallow spiral ramp which links the building ‘s levels leading first to Hadrian’s funerary chamber 10mt higher than the vestibulum. Much of this is in a fine state of preservation and includes patches of its original black and white mosaic decoration.
The mausoleum was used as the resting place of emperors until the death of Settimio Severo at the beginning of the 3rd century. On top of the drum was a soil tumulus and crowning this was a gilded chariot driven by a vast statue of Hadrian. In the V century the mausoleum was incorporated by Honorius into the Aurelian Walls. Since then the mausoleum took the name of Castellum (castle). In 537 A.D. during the invasions of the Goths led by Vitige it became one of the strongest fortress and even the many statues which decorated the monument were used as weapons against the enemy! Around the 10th century it was transformed into a castle and residence: fortified by Crescenzio, member of the family of Alberico, it took the name of castrum Crescentii.
Teodorico transformed it into a prison (Carceres Theodorici) and it kept this function even under the papal and then the Italian government, until 1901. The statue of the angel, after which the castle is named was put on the top of it after a vision by pope Gregory the Great, who whilst leading a procession through Rome to pray for the end of a plague saw an angel sheating a sword, an act thought to symbolize the end of the pestilence.
Beside the statue of the angel is the Bell of the Misericordia (mercy), which announced the capital executions. The bronze statue of the angel crowning the battlements today was made by Pietro van Verschaffelt: it is the sixth of a series. The first in wood was substituted by consuption, the second one in marble fell down and broke into pieces, the fourth, in bronze, was melted for the cannons used in 1527, during the sack of Rome, the fifth, in marble with wooden wings, is today housed in the courtyard of the balls (so named after the cannonballs of different sizes here on display). The sixth one was painted by the French army with the colours of France during the invasion in 1798.
In the Capitoline Museums is also on display a stone upon which it is possible to see the foot print of the Angel when he stopped to announce the end of the plague. In 1277 the castle was linked with the Vatican by way of a covered passage known as the “passetto”.
The prisons were terrible, accounts survive of the tortures inflicted in its dungeons, and of the famous prisoners such as Benvenuto Cellini, incarcerated in its notorious San Marocco Cell. He tried to escape but in vain and when closed in the underground cells he painted a Christ on the wall of which we still have some remains. In the funeray chamber of the emperors took refuge Cola di Rienzo in 1347 and pope Clement VII during the sack.
Under Leo X and Pius IV representations were staged here and till the first years of last century the Girandola, a firework created by Michelangelo himself was lit up here. Today the castle houses a museum and its rooms are splendidly decorated.
How to reach: Metro Line A, stop at Lepanto, Ottaviano-San Pietro. Bus: lines 62, 23, 271, 982, 280 (get off at Piazza Pia) line 40 (terminus Piazza Pia) line 34 (stop Via di Porta Castello) lines 49, 87, 926 , 990 (Piazza Cavour terminus-stop via Crescenzio) lines 64, 46.