Atlantic Plain
The plain is not very high, averaging around 900 or less feet from sea level. It extends about 50 to 100 kilometers inland. The coastal plain is very wet, with many rivers, marshes, and swampland. It is composed mainly of sedimentary rock and sediment, and the land is usually used for agriculture. The coastal plain also has the Carolina Sandhills as well. Sometimes, on maps, the coastal plain is split into two northern and southern regions. Sea levels rising is also an issue, because ocean water (Or salty water) starts to kill plants that can't use saltwater in photosynthesis. Groundwater supplies are also vulnerable along the East Coast. With industrial and urban development (like houses, factories, and roads), many inland salt (with saltwater) marshes are disappearing.