Where is the largest volcano in the solar system?

The largest volcano in the solar system is Olympus Mons, located on Mars. It is about 600 kilometers (373 miles) in diameter and stands roughly 22 kilometers (13.6 miles) high. Olympus Mons is a shield volcano, formed by the slow eruption of lava over millions of years. Its size is a result of Mars’ lower gravity and the lack of tectonic plate movement, allowing lava to accumulate in one spot and form such a massive structure.