Peña de Bernal, Monolithic summit in San Sebastian Bernal, Mexico.

Peña de Bernal is a dacitic dome, the exposed core of an extinct volcano, rising 350 metres above the village of Bernal in Ezequiel Montes, Querétaro, at 2,515 metres above sea level. Its upper part is bare pale grey and tan rock with vertical ridges and deep crevices; green scrub and scattered trees cover the lower slopes, and a lower rocky shoulder extends to the left.

Peña de Bernal is the exposed core of an extinct volcano: viscous, nearly solid lava pushed up through older marine rocks and solidified underground as a dacitic dome. Chemical analysis by researchers at the National Autonomous University of Mexico dated it to about 8.7 million years ago, far younger than the Jurassic age once assumed. Erosion of the surrounding cone left the spine standing above the village of Bernal, founded at its foot in 1641.

The name Bernal comes from an Almería term the conquerors used for a large, elongated isolated crag; in Otomí the peak is Ma'hando and in Chichimeca De'hendo, both meaning "between two". On 21 March, the spring equinox, thousands gather at the rock for a mystic-religious festival, seeking to "recharge energy" from the monolith. In 2009 UNESCO inscribed the Otomí-Chichimeca memory places of Tolimán, with the Peña as guardian of a sacred territory, on its Intangible Heritage list.

Hiking paths start in the village and lead up to about halfway, with the first sections manageable for most visitors. The route becomes steeper and later requires climbing gear for further ascent.

In September 2009 UNESCO inscribed the Otomí-Chichimeca memory places and living traditions of Tolimán, naming the Peña de Bernal as guardian of a sacred territory. A plaque at the start of the trail marks its 2007 selection as one of the 13 Wonders of Mexico by the Tourism Secretariat and TV Azteca.