Olympus Mons is 100 times larger. It covers an area 373 miles (600 kilometers) across, about the size of the state of Arizona, and its summit is 17 miles (27 kilometers) high. That is twice the ...

At its summit is a spectacular depression some 53 miles (85 km) wide, formed by magma chambers that lost lava (likely during an eruption) and collapsed. While you're climbing around Olympus Mons ...

Mt. Everest might be the tallest mountain on Earth, but it's nothing compared to the tallest volcanic mountain in the solar system, Olympus Mons on our red cousin Mars. John Brady at Astronomy ...