Olympus Mons from Orbit.

Olympus Mons on Mars is the largest volcano in the Solar System . Although three times higher than Earth's Mount Everest , Olympus Mons would not be difficult to climb because of the volcano's great breadth. Covering an area greater than the entire Hawaiian volcano chain , the slopes of Olympus Mons typically rise only a few degrees at a time. The low gravity of Mars combined with a relatively static surface crust allow volcanoes this large to build up over time. This representative-color image was taken last April by the Mars Global Surveyor spacecraft currently orbiting Mars.