The tallest free standing rock in the world is in Mexico, in the state of Querétaro.
It is the Peña de Bernal Natural Monument, and stands at an impressive 433 meters (1,421 feet) high, making it the tallest freestanding rock.
It is the grand entrance to the Sierra Gorda, a mountainous region that the United Nations Educational, Scientific, and Cultural Organization not long ago declared a Biosphere Reserve. Even more recently, in 2009, the rock itself was given the status of an Intangible Cultural Heritage site by UNESCO.
Still, it is not a household name, and the origins remain largely a mystery.
Mexican Monolith Is World's Tallest Freestanding Rock by Crystal Gammon, OurAmazingPlanet Contributor | LiveScience.com – Thu, May 9, 2013: