Tharsis quadrangle Mount Everest and about as big in area as all of Europe. Tharsis contains a group of large volcanoes. Olympus Mons is the tallest. Tharsis is a land of great volcanoes. Olympus Mons is the tallest known volcano in the Solar System; it is 100 times larger than any volcano on Earth. Ascraeus Mons and Pavonis Mons are at least 200 miles across and are over six miles above the plateau that they sit on—and, the plateau is three to four miles above the zero altitude of Mars. Pavonis Mons, the middle in a line of three volcanoes, sits at
Doom Mons Doom Mons Doom Mons is the name of a mountain range and its eponymous peak on Titan, the largest moon of Saturn. A putative cryovolcano, it is the largest mountain range on Titan by volume, and its 1.45 km-high peak one of the highest. It was discovered by the "Cassini–Huygens" probe in 2005 and officially named in 2012. Doom Mons is located in the Southern Hemisphere of Titan, between 14-15° south and 40-41° west. It is located within the Aztlan darklands region, possibly connected to the wider Shangri-La dark region, and is adjacent to Sotra Patera, a possible cryovolcanic caldera