The Furlo Gorge, also known as pass of the Furlo Gorge, is situated along the original path of the via Flaminia, passing alongside the Candigliano river an affluence of the Metauro river in the area of Pesaro-Urbino.
The Gorge was formed between the Pietralata (889 m) and the Paganuccio (976 m) mounts due to the erosive force of the Candigliano river, over the millennia it has achieved a remarkable depth that nowadays is no longer visible due to the dam, built in 1922, which made the impetuous watercourse a placid lake.
By the Environment Ministry Decree dated February 6th 2001 was established the Furlo Gorge public natural reserve.

To allow people and vehicles a smooth passage, Emperor Vespasian let dig, a gallery in the narrowest point of the Gorge which was called "petra pertusa" or forulum (small hole), from which "Furlo"; next to it there is a previous passage, 8 m long, 3,30 m wide, 4.45 m high of Etruscan era and a small church called "of the barrel", once inhabited by an hermit.

Above the North-East entrance is still visible the inscription: "IMP. CAESAR AUG. – VESPASIANUM PONT. MAX – TRIB. POT. VII IMP. XVII PP. COS. VIII – CENSOR FACIUND CURAVIT" (the last straight stroke of the sign VIII is probably an addition), establishing the fulfillment of the work between 76 and 77 after Christ.
The Gallery has a length of 38,30 m, a maximum wideness 5.47 m and a highness of 5.95 m; It's all dug in compact limestone by using a chisel, still visible the gradine cuts and it is without coating.

In the 1980s, for the fast traffic, the Furlo was bypassed by an highway with two new galleries with a length of 3391 m, giving back the gorge to the joy of its admirers.
In the 1930s the local forester sculpted on the slopes of the Pietralata mount, behind the gorge, the profile of Benito Mussolini.

A tribute in his honor who often passed through the Gorge in his travel from Rome to the Northern of Italy.
The monument was undermined and destroyed by partisans during the war, nowadays only few ruins are recognizable.