Three colossal volcanoes standing in a perfect diagonal row.
Tharsis Montes is a chain of three enormous shield volcanoes — Arsia, Pavonis and Ascraeus Mons — lined up along the crest of the Tharsis rise. Each towers roughly 10–18 km high, and together they anchor the largest volcanic province on Mars.
Claim your plot here →The three Tharsis Montes rise in a strikingly straight diagonal line, each summit crowned by a broad summit caldera. From southwest to northeast they are Arsia Mons, Pavonis Mons and Ascraeus Mons, with Pavonis sitting almost exactly on the Martian equator. Their alignment traces a fundamental fracture in the crust that channeled magma to the surface for billions of years.
These volcanoes sit on the Tharsis bulge, a continent-scale swell of the crust so massive it may have shifted the planet's spin axis and pumped gases into the early atmosphere. Nearby stands Olympus Mons, the tallest of all, just to the northwest. The Montes' flanks preserve vast lava fields, and clouds of water ice frequently form over their summits in the Martian afternoon.
Like Hawaii's volcanoes lined up over a hotspot — but each Tharsis peak dwarfs the entire island of Hawaii.
Olympus is taller and stands apart, but the three Montes together dominate a far larger stretch of the bulge.