Coastal plain

Coastal plains can form in one of two ways; some begin as a continental shelf, a flat piece of land located below sea level, and are created when the ocean level falls, exposing the land. Others develop when river currents carry sediment into the ocean, which is deposited and builds up over time until it forms a coastal plain. They are generally separated from the rest of the interior by proximate landforms, like mountains. ==Locations==

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 . The Atlantic Coastal Plain runs from the New York Bight to Florida. Another is the Swan Coastal Plain in Western Australia, which includes the city of Perth. It is one of the distinct physiographic provinces of the larger West Australian Shield division. == See also ==