The largest volcano in the solar system is Olympus Mons, located on Mars. This colossal shield volcano stands about 13.6 miles (22 kilometers) high, making it nearly three times the height of Mount Everest. Olympus Mons is approximately 370 miles (600 kilometers) in diameter, featuring a broad, gently sloping profile typical of shield volcanoes formed by the eruption of low-viscosity lava. The volcano also has a vast caldera at its summit, measuring about 50 miles (80 kilometers) across. Its immense size and unique geological features offer insight into the volcanic activity and planetary history of Mars.