Olympus Mons (; Latin for 'Mount Olympus') is a large shield volcano on Mars. It is over 21.9 km (13.6 mi; 72,000 ft) high as measured by the Mars Orbiter Laser Altimeter (MOLA), about 2.5 times the elevation of Mount Everest above sea level. It is Mars's tallest volcano, its tallest planetary mountain, and is approximately tied with Rheasilvia...