The Underground Basilica of Porta Maggiore – Decorated with exquisitely crafted stuccoes and dedicated to the Neo-Pythagorean cult, this refined jewel of private architecture from the Augustan era remained buried and unknown for 19 centuries. Until it was discovered in 1917, during work on the railway. Although small in size (12 metres long by 9 metres wide, for a total of 108 m2), it already presents the classical scheme of a central nave with side wings divided by pillars plus the apse at the back, which would later be used for Christian worship. The complex is articulated in three different environments.
