Monte Sibilla, Mountain summit in Province of Ascoli Piceno, Italy

Monte Sibilla is a 2,175-metre limestone peak in the Sibillini Mountains, on the border of the municipalities of Montemonaco and Montefortino within the Monti Sibillini National Park. Its summit is ringed by steep pinkish rock that forms a wall-like "crown", and the Sibilla Refuge stands on the mountain. Near the top, at 2,173 metres, opens the Grotta della Sibilla.

The mountain was the site of a pagan cult of Cybele, the great mother of the gods, which spread in the time of Claudius. With Christianity, the cult of the Sibyl replaced it, identified in the 14th century as the Cumaean Sibyl and later as the Apennine Sibyl. In May 1420 Antoine de la Sale climbed the summit from Montemonaco and described the Sibyl's grotto in Le Paradis de la Reine Sibylle.

The name comes from the Sibyl, a figure identified in the 14th century as the Cumaean Sibyl and in more recent studies as the Apennine Sibyl, who was not among the eleven listed by Varro. The cave near the summit, at 2,173 m, was the site of the pagan cult of Cybele, the Great Mother of the gods, which spread in the time of Claudius; with Christianity, the cult of the Sibyl replaced it. The legend reached a wide public through Andrea da Barberino's Il Guerrin Meschino and was reworked by Richard Wagner in Tannhäuser.

Reaching the top requires a strong level of fitness and comfort with heights, as the route from Refugio Sibilla involves steep sections with metal chains fixed to the rock. The route is typically snow-free and most accessible from late spring through early autumn.

Antoine de la Sale climbed Monte Sibilla from Montemonaco in May 1420 and drew a plan of the Sibilla cave, now kept at the Bibliothèque nationale in Paris. He described a wide space ringed by benches cut into the rock, which he called "intalieux tout entour". The cave mouth lies at 2,173 m, just below the 2,175 m summit.