Mont Denise, Volcanic summit in Haute-Loire, France

Mont Denise rises to 892 meters between Espaly-Saint-Marcel and Polignac, with distinctive basalt columns reaching about 20 meters high. The area mixes volcanic formations with meadows and forests crossed by maintained hiking trails.

In 1844, a man working his vineyard in the volcanic ash on the mountain found human bones, which were attributed to the "Man of Denise". In 1591, violent fighting reached the summit between the royalists of Polignac and Espaly and the Leaguers of Le Puy.

The name Denise comes from the "Homme de la Denise", the human bones found in the volcanic ash in 1844. The summit lawns were grazed until the 2000s, then abandoned; since late 2020 the CEN Auvergne has put them back under grazing. The cave shelters seven bat species, monitored by naturalists since 1928.

The summit, at 892 metres, carries a telecommunications mast, and the southern flank holds a disused quarry that cut open the volcanic cone. The cave of la Denise is a fissured underground passage penetrable by humans for only about thirty metres. The summit lawns, grazed until the 2000s and then abandoned, were put back to grazing by the CEN Auvergne at the end of 2020.

The mountain hosts seven bat species in the Denise cave, with six designated as conservation priorities in European wildlife programs. These creatures use the cave systems for shelter and make the location an important refuge in the region.