The Appalachian Mountains are of the oldest mountain ranges in the whole world. When they were at their peak, they were as high as the Rocky Mountains in the present.
Nowadays, we see a different picture of the Appalachians. They are lower and more gently steeped. This is a result of the millions of years of erosion. Once the ''growing'' of the Appalachians stopped, the erosion started to dominate. As the erosion, from wind, water, heat, ice, started to take place, little by little the mountains started to lose on height, but also to become less steep. Since the erosion has the tendency to flatten the terrain, it will continue to make the Appalachians smaller and smaller as the time passes, until it totally flattens them somewhere in the distant future.
