In 2006 excavations began on the Etrusco-Roman settlement of Coriglia, undertaken by Saint Anselm College (NH) in collaboration with the municipality of Castel Viscardo. The investigations brought to light a series of structures situated on a terrace overlooking the valley of the river Paglia, a tributary of the Tiber, beside the via Traiana Nova. One of the trenches produced evidence of both the Etruscan phase, with 6th century B.C. tufa structures and grey bucchero, and the late Roman period in the form of an imposing wall belonging to a substructure on an east-west alignment. Further north another wall was exposed belonging to a part of a building overlooking the valley. This was divided into three parts, with channels and bath structures. Use of this building began in the Republican period and ended in the second half of the 3rd century A.D., as attested by coins of Gallienus (253-268) and Claudius the Goth (270). A trench opened in the 1990s (SAU) revealed a section of a wall crossing the excavation area on an east-west alignment.

Immediately south of the wall, on the same level, there was a cobbled surface with stones of considerable size, separated from the wall by a layer of reddish earth which in the 1990s produced Hellenistic material. In 2009 a new trench was opened to the south. This exposed part of a tank, its facing of small slabs showing lime concretions (XRF analysis confirmed the presence of iron, lime and potassium) indicating contact with water. The excavation data and archeometric technologies (XRF and Raman) indicated more specifically that this water was sulphureous.

This was a monumental complex of Roman date, with spectacular terraced architecture, linked to the exploitation of thermal waters. It was built on top of pre-existing Etruscan structures which at the moment are of an unknown nature.