The Hypogeum was the Roman-Etruscan tomb of Arnth Veltimna Aules. It is part of the larger Palazzone necropolis, a burial ground dating to the 6th-5th century BC, with numerous subterranean tombs. A museum building displays funerary urns and other artifacts found in the excavations of the area. More urns are displayed in the separate building covering the Volumnus tomb. The Volumnus tomb itself is accessed by a staircase which leads several metres under the surface to the portal leading inside to a vestibule. This in turn opens into four small side chambers and three larger central ones, the middle of which housed the remains of the family’s main members. Only this chamber now displays burial urns and artifacts. Arnth’s urn is made of travertine, and is surmounted by a representation of the deceased lying on a triclinium.