INTERCISA
INTERCISA or AD INTERCISA, is the name given in the Itineraries to a station on the Via Flamninia, which evidently derives this name from its being situated at the remarkable tunnel or gallery hewn through the rock, now known as the Passo del Furlo. (Itin. Hier. p. 614; Tab. Peut.) This passage, which is still traversed by the modern highway from Rome to Fano, is a work of the emperor Vespasian, as an inscription cut in the rock informs us, and was constructed in the seventh year of his reign, A. D. 75. (Inscr. ap. Cluver, Ital. p. 619.) It is also noticed among the public works of that emperor by Aurelius Victor, who calls it Petra Pertusa; and the same name (Πέτρα περτοῦσα) is given to it by Procopius, who has left us a detailed and accurate description of the locality. (Vict. Caes. 9, Epit. 9; Procop. B. G. 2.11.)The valley of the Cantiano, a tributary of the Metaurus, which is here followed by the Flaminian Way, is at this point so narrow that it is only by cutting the road out of the solid rock that it can be carried along the face of the precipice, and, in addition to this, the rock itself is in one place pierced by an arched gallery or tunnel, which gave rise to the name of Petra Pertusa. The actual tunnel is only 126 feet long, but the whole length of the pass is about half a mile. Claudian alludes to this remarkable work in terms which prove the admiration that it excited. (Claud. de VI. Cons. Hon. 502.) At a later period the pass was guarded by a fort, which, from its completely commanding the Flaminian Way, became a military post of importance, and is repeatedly mentioned during the wars of the Goths [p. 2.57]with the generals of Justinian. (Procop. B. G. 2.11, 3.6, 4.28, 34.) The Jerusalem Itinerary places the station of Intercisa 9 M. P. from Calles (Cagli), and the same distance from Forum Sempronii (Fossombrone), both of which distances are just about correct. (D'Anville, Analyse de l'Italie, p. 155.)
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