It is an archaeological site where the remains of a medieval city built in the mid-ninth century and abandoned in the modern age were excavated.
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According to what is reported in the Liber Pontificalis, the city was founded by Pope Leo IV on August 15 of the year 854 to give a safer seat to the citizens of Centumcellae (Civitavecchia) and its diocese, as the city was hit by the raids of the Saracens on the coast Tyrrhenian. According to his biographer, the pope would have given the new city the name of Lviv, but in all the documents we find, in the first centuries, the name of Centumcellae - civitas or castrum centumcellensis, later changed to Centucelle - Cincelle - Cencelle.
The new city was founded on a branch of the Via Aurelia, on an easily defensible hill between the river Mignone and its tributary Melledra, which had also been occupied in ancient times by the Etruscans [2]. At the time of the foundation, the city walls were built, a first church, an episcopal seat, with an adjoining cemetery and wooden houses, subsequently replaced by masonry houses and palaces. The main church dedicated to San Pietro was rebuilt larger between the end of the 11th and the beginning of the 12th century.
The city was damaged by the earthquake of 1349 and the buildings were subsequently restored. It gradually decayed and at the beginning of the 15th century the lands were "destroyed and uninhabited" according to sources. In the second half of the fifteenth century the town area was used for the exploitation of the alum mines of the Tolfa mountains and in the seventeenth century it was probably the center of a farm.
The site has been the subject of excavation campaigns conducted by the chair of medieval archeology of Sapienza - University of Rome by Letizia Pani Ermini since 1994, in collaboration with several other universities and research institutes. The excavation is directed by Francesca Romana Stasolla.