Highest cliffs in the Solar System
Verona Rupes
(Miranda, satellite of Uranus.)

NASA's Voyager 2 probe encountered the planet Uranus and its collection of moons in 1986. The small moon Miranda, with a diameter of 472 km, has a surface made up of a jumble of bizarre geological features. One of the most prominent of these features is an enormous cliff with a vertical relief of about 20km 12 miles. This cliff, named Verona Rupes, is more than ten times higher than the walls of the Grand Canyon on Earth. That this towering cliff is so huge is made even more remarkable by the small size of Miranda itself. The white material exposed in the cliff face is probably mostly water ice.