Geology of Mars of the dichotomy places a significant constraint on theories of its origin. Straddling the dichotomy boundary in Mars's western hemisphere is a massive volcano-tectonic province known as the Tharsis region or the Tharsis bulge. This immense, elevated structure is thousands of kilometers in diameter and covers up to 25% of the planet’s surface. Averaging 7–10 km above datum (Martian "sea" level), Tharsis contains the highest elevations on the planet and the largest known volcanoes in the Solar System. Three enormous volcanoes, Ascraeus Mons, Pavonis Mons, and Arsia Mons (collectively known as the Tharsis Montes), sit aligned NE-SW along the crest
Olympus Mountain Running run. From a boat the competition starts, the swimming ends at the beach of Platamonas. The route depends on the wind direction, the athletes are accompanied by boats. From Platamonas, the Olymp is almost completely rounded. The cycle race takes place on paved roads, 4100 vertical meters have to be overcome. Target is the place Vrisopoules. From Vrisopoules, the route leads over the second highest peak of the mountains (Skolio, 2911 m) on forest roads down to the river Orlias, which is the destination of the triathlon. There are 2250 vertical meters to overcome. Olympus Mountain Running Since 1986, nearly