In 1935 Desiderato Scenna discovered the remains of four ancient Roman temples, the best-preserved one of which was used as a church since the 8th century and renamed after Saint Peter and Saint Paul, whereas another one has been removed to build a post office. The construction of the two twin temples and the smaller one was commissioned by Marcus Vetius Marcellus and his wife Helvidia Priscilla, who were favored by Nero. They do not know what divinities they were dedicated to, even if some scholars proposed that they were consecrated to the Capitoline Triad (Jupiter, Juno and Minerva). The walls are made of bricks, marble slabs, stone slabs and stone tiles, and the plan of the twin temples included a portico and underground spaces.