What forms the border between the piedmont and coastal plain?

There are three distinct landforms of the Southeast and of North Carolina: the Coastal Plain, the Piedmont, and the Appalachian Mountains.

The Coastal Plain is low, flat to gently sloping land that extends along the Atlantic Ocean and the Gulf of Mexico. Much of the Southeast lies within in the Coastal Plain.

The Piedmont, characterized by hilly, rolling land, borders the Coastal Plain. The Piedmont extends from Virginia to Alabama.

The Appalachian Mountains, the largest range in the eastern United States, stretch from Canada to northern Alabama.

the answer is richard nixion