Volcanoes, earthquakes and many of the great, in size, mountains (the Himalayas, Rockies, Urals, Alps, and the Appalachians) will all be marked on my map at some point in this project. Now just let me tell you some interesting facts about some of these topics. Since recorded history, 550 volcanoes have erupted on the earth’s surface, but even far more have erupted unobserved on the ocean floor.