The Tharsis Rise is the largest volcanic and tectonic feature on Mars. Here crustal materials have been pulled and broken apart to form troughs, and pushed together and buckled to form ridges. Some Tharsis landforms, such as the Olympus Mons volcano, 26 kilometers (15.5 miles) high, and the Valles Marineris canyon system, are the largest in the solar system. Valles Marineris, named after the Mariner 9 probe that first photographed it, is up to 8 kilometers (5 miles) deep and 4,500 kilometers (2,800 miles) long. The Grand Canyon could easily fit into one of its side canyons.