The Outer Banks is a string of peninsulas and barrier islands separating the Atlantic Ocean from mainland North Carolina. From north to south, the largest of these include: Bodie Island (which used to be an island but is now a peninsula due to tropical storms and hurricanes), Hatteras Island, Ocracoke Island, Portsmouth Island, and the Core Banks. Over time, the exact number of islands and inlets changes as new inlets are opened up, often during a breach created during violent storms, and older inlets close, usually due to gradually shifting sands during the dynamic processes of beach evolution.