Geography of Mars Aurorae Sinus. The largest dark feature seen from Earth is Syrtis Major Planum. The shield volcano, Olympus Mons ("Mount Olympus"), rises 22 km above the surrounding volcanic plains, and is the highest known mountain on any planet in the solar system. It is in a vast upland region called Tharsis, which contains several large volcanos. See list of mountains on Mars. The Tharsis region of Mars also has the solar system's largest canyon system, Valles Marineris or the "Mariner Valley", which is 4,000 km long and 7 km deep. Mars is also scarred by countless impact craters. The largest of
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