Il Ponte Sfondato sul torrente Farfa (Sabina, Lazio)

Marco Pantaloni (1) & Fabiana Console (2)
(1) Servizio Geologico d'Italia, ISPRA, via V. Brancati 48 - 00144 Roma. orcid: 0000-0002-8148-9164. (2) Biblioteca, ISPRA, via V. Brancati 48 - 00144 Roma. orcid: 0000-0002-7448-8606. Corresponding author e-mail: marco.pantaloni@isprambiente.it

Ponte Sfondato is a hamlet of Montopoli di Sabina, Rieti; this name derives from a natural arch on the Farfa river, originating from a particular type of erosive phenomenon. This paramount landform and its formation represent an intriguing history. The Ponte Sfondato was a unique example of geomorphosite formed by the erosion of a long rocky relief originating from the over-excavation of a recessed meander. The lithology of the relief, characterized by the presence of weakly cemented gravel with arenaceous levels, has facilitated the erosive activity of the Farfa river. It has been able to “break through” the rocky promontory causing the formation of the arch, creating a water path below. The natural arc has a high degree of instability; vertime, in fact, this particular morphotype tends to thin out and collapse. The arch was used for traffic road until 1960 when it was replace by a modern bridge and it collapsed in 1961. Ponte Sfondato is a place of geological-historical memory, representing an important site of geological-landscape interest. Because of its evolution, this site is no longer visible and it remains in the collective imagination through writings, maps, publications, paintings, and also through mentions in novels, pictures and movies.

Storia della geologia, Arco naturale, torrente Farfa, Sabina, Lazio