Piedmont (United States)
The Piedmont is mainly an area of relatively low, rolling hills. They have a height above sea level between 200 feet (50 m) to 1,000 feet (300 m). Its geology is complex. THere are many rock formations of different materials and ages. The Piedmont is the remains of several old mountain chains. Geologists say at least five separate events led to sediment being depositted. These include the Grenville orogeny  and the Appalachian orogeny. The last major event in the history of the Piedmont was the break-up of Pangaea. This was when North America and Africa began to separate.