Mars is home to Olympus Mons (pictured above), the largest volcano in the solar system. Rising 21-24 km from the surrounding area, Olympus Mons is the dominant spot in the Tharsis region, which is the largest topographic feature on the planet. The Tharsis volcanic province covers close to 25% of the planet’s surface and houses twelve large volcanic constructs.
Besides the Tharsis region, Syrtis Major, the Elysium complex, Apollinaris Mons, and the Hellas Basin are also home to volcanic provenances.
Volcanism on Mars was extremely long-lived and extensive. It’s estimated that Mars had active volcanism from 3.9 billion years ago to as recently as 150-100 million years ago. That means that as the dinosaurs were roaming the Earth, volcanoes were still erupting on Mars!
Emily Zawacki, Ph.D. 