Coastal plain

Area of flat, low-lying land adjacent to a seacoast

A coastal plain is flat, low-lying land adjacent to a sea coast. A fall line commonly marks the border between a coastal plain and a piedmont area. Some of the largest coastal plains are in Alaska and the southeastern United States. The Gulf Coastal Plain of North America extends northwards from the Gulf of Mexico along the Lower Mississippi River to the Ohio River, which is a distance of about 981 miles (1,579 km). The Atlantic Coastal Plain runs from the New York Bight to Florida.

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