Caldera and Elysium. Each province contains a series of giant shield volcanoes that are similar to what we see on Earth and likely are the result of mantle hot spots. The surfaces are dominated by lava flows, and all have one or more collapse calderas. Mars has the largest volcano in the Solar System, Olympus Mons, which is more than three times the height of Mount Everest, with a diameter of 520 km (323 miles). The summit of the mountain has six nested calderas. Because there is no plate tectonics on Venus, heat is mainly lost by conduction through the lithosphere.
Olympus Mountain Running The medical care is provided by rescue services. The fastest runners finishes the race in about four hours. Around 1970, inspired by mountain running in the Alps, the first thoughts of a marathon in Olympus came on. Younger members of the Mountaineering Association E.O.S. Thessaloniki implemented the idea; a running track was selected, the paths were cleaned and marked. The first run took place on July 6, 1986. Around 100 Greek runners participated; although starting numbers have been assigned, there are no statistics on the results of this first Olympus Marathon. The new sport was called "Mountaineer Marathon", not only