Mountain chain of southern Lazio, situated between the course of Liri-Garigliano, the Tyrrhenian Sea, and the adjacent massif of Ausoni Mountains. The Park involves the territory of the Municipalities of Ausonia, Campodimele, Esperia, Fondi, Formia, Itri, Lenola, Pico, Pontecorvo, Spigno Saturnia, between the Provinces of Latina and Frosinone.