The Mignone River runs through this hilly countryside, rich in plant and animal life, situated between Tarquinia and the Tolfa Mountains. In the 16th century, it became the property of the Farnese family, who then developed the area into flourishing farmlands. Today, most of this territory belongs to the Università Agraria di Tarquinia (Agricultural University of Tarqunia) and is primarily used for raising cattle in the wild.
This city was founded by Leo IV (August 15th, 854 according to Papal records) in the territory of Tarquinia near the Mignone River in order to save the inhabitants of Centumcellae (modern-day Civitavecchia) from Saracen invasions. Leopoli-Cencelle was a bishopric for five centuries. Yearly archaeological digs have unearthed the remains of buildings, churches, tombs artifacts.