Where is the largest known volcano in the Solar System?

Olympus Mons is the largest known volcano in the Solar System, and it is located on Mars. It stands about 22 kilometers high, nearly three times the height of Mount Everest above sea level, and spans roughly 600 kilometers across. Scientists think it grew so large because Mars has much lower gravity than Earth and lacks plate tectonics like our planet. Its slopes are relatively gentle because it is a shield volcano built by repeated fluid lava flows. Olympus Mons is one of the most famous landmarks on Mars and a key target in planetary science.