The Roman cistern leads the visitor into the underground Amelia, exactly under the current Piazza Matteotti, corresponding to the ancient Roman forum. The imposing building is composed of a large rectangular room dug into the limestone rock and divided into ten parallel communicating rooms, covered with barrel vaults and covered with small stone walls (opus incertum).

The complex constitutes one of the best examples of the Romanization process undergone by the small Umbrian center around the 1st century BC. It was built to collect rainwater for drinking use. Very well preserved, it has maintained all its fundamental components: the water inlet system, the internal device for regulating its level and the tank emptying system.

In a corner of the first room a small portion of flooring, made with bricks, is preserved. Interesting is the presence of the stamp with the name of the owner of the brick factory, Caius Atilius Fortunatus.