* Mountain - A large, elevated area of land that rises abruptly from the surrounding terrain. Mountains are formed by the movement of tectonic plates, which can cause the land to fold, buckle, and uplift.

* Valley - A low area of land that is surrounded by higher terrain. Valleys are often formed by the erosion of water or ice over time.

* Canyon - A deep, narrow valley with steep sides. Canyons are often formed by the erosion of water or ice over time.

* Plateau - A large, flat area of land that is elevated above the surrounding terrain. Plateaus are often formed by the erosion of water or ice over time.

* Mesa - A flat-topped hill with steep sides. Mesas are often formed by the erosion of water or ice over time.

* Butte - A small, isolated hill with steep sides. Buttes are often formed by the erosion of water or ice over time.

* Cliff - A steep, vertical face of rock. Cliffs are often formed by the erosion of water or ice over time.

* Glacier - A large mass of ice that forms on land and moves slowly over time. Glaciers are formed by the accumulation of snow over time.