Exploratour - Comparing the Surfaces of Earth and Mars
The graph to the left compares the size of the highest peaks of Earth and Mars. Mars Global Surveyor measured the size of Olympus Mons. Height is shown in meters on the left-hand axis. The height of Mt. Everest is also shown. You can see that Olympus Mons is much higher than Mt. Everest (and Mauna Loa, from the ocean floor up!). Olympus Mons is also wider than the entire chain of Hawaiian Islands.