Archaeological field survey has been carried out in the area of Pietroso, revealing a Roman landscape with a dense scatter of farms and necropoleis, linked by a branch of the via Flaminia still partially in use today. The choice of the area of Monte Petrolo for the creation of a large industrial area by the commune of Rignano Flaminia, happened by coincidence to fall on an ancient settlement with an equally industrial character, a fact mentioned by the Soprintendenza in its written opinion before planning permission was granted.

The massive earth-moving operations of 2000 and subsequent archaeological investigations have revealed a large number of structures that document the Roman occupation of the site. These are a series of kilns, of various sizes, arranged along a road originally connected to the branch of the Flaminia mentioned above. There are also various hydraulic infrastructures, including cuniculi and cisterns, as well as what might be interpreted as vats for the preparation of clay, and various structures near the kilns destined for workshops or storage facilities.

Furture investigations should further clarify the characteristics of this clearly industrial complex, and render its chronology more precise.