The monument was named Castel Sant'Angelo because of a legend. In the fifth century, there was a great plague in Rome. Pope Leo I saw a vision of the Archangel Michael sheathing his sword, a sign that the plague was about to end. Today, there is a statue of the angel over the castle, the site of the vision (see photo above). The Ponte Sant'Angelo, the bridge crossing the Tiber to the castle, has remnants of one of the oldest bridges in Rome.
