Foothill

Foothills are geographically defined as gradual increase in elevation at the base of a mountain range, higher hill range or an upland area. They are a transition zone between plains and low relief hills to the adjacent topographically higher mountains, hills, and uplands.

Foothills primarily border mountains, especially those which are reached through low ridges that increase in size closer and closer to the mountain, but can also border uplands and higher hills.

Areas where foothills exist, or areas commonly referred to as the foothills, include:

Another word for a foothill region is "piedmont", derived from "foot of the mount" in Romance languages. The Piedmont region of Italy lies in the foothills of the Alps, and several other foothills in other parts of the world are .

They are also known as submontane zones, especially when referring to montane ecosystems.

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