Mountains on Earth are able to rise when the "root" of the mountain is sufficiently supported by the rocky (Earths crust is made of rock, not water) but pliable (it is also warm and flexible) mantle beneath the surface. The process is somewhat akin to the way in which an iceberg floating in the open sea exposes only the upper third of its volume. If the material in which the root is floating is strong enough, it can allow more of the tip to be exposed above the surface.
You may leave the tour and read more about the process of erosion, the process of mountain building, or the qualities of the Earth's mantle by using the links found at the bottom of this page.
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