The Hermitage of the SS. Trinità di Allumiere is one of the oldest monasteries in the Roman Province and has existed, according to some historians, since the time of Gregory IV, who lived in the 9th century. The structure is immersed in tranquility and silence and is characterized by a simple and sober construction. Recent archaeological findings confirm the hypothesis of its existence since the time of St. Augustine and his stay in the Centumcellae area in the 4th century AD.

The discovery of Roman artefacts, columns, capitals and bricks, some of which bear the factory stamp of the Emperor Trajan, make it highly probable that the construction of the Hermitage was carried out, using pre-existing structures and relevant materials, probably for a small temple dedicated to the water nymphs.

In fact, it is precisely in this area that one of the largest water basins is located, from which the springs were collected that were to supply excellent drinking water to the port of Trajan in Centumcellae, which was being built at the beginning of the 2nd century AD.

Also in order to document the possibility of a stay of St. Augustine in this Hermitage, an archaeological campaign was undertaken by the Adolfo Klitsche de la Grange Archaeological Association of Allumiere, in close collaboration with the Archaeological Superintendency for the province of Viterbo and Southen Etruria.