- The Castel Sant'Angelo (Castle of the Holy Angel; Chateau Saint-Ange; Die Engelsburg ) is a towering cylindrical building in Rome.Construction: 123-139 AD; commissioned by the Roman Emperor Hadrian as a mausoleum for himself and his family. (Mausoleum of Hadrian; Mausol閑 d'Hadrien; Mausoleum des Kaisers Hadrian; Mausoleo di Adriano). The building was later used by the popes as a fortress and castle; and is now a museum. (Museo Nazionale di Castel Sant'Angelo)- Ponte Sant'Angelo (Bridge Sant'Angelo; Pont Saint-Ange; Engelsbr點keu ) originally the Aelian Bridge or Pons Aelius; is a Roman bridge completed in 134 AD by Roman Emperor Hadrian (Publius Aelius Hadrianus); to span the Tiber from the city centre to his newly constructed mausoleum; now the towering Castel Sant'Angelo.Since the 17th century ten statues of angels are on the bridge.Rome; Italy. 2020.