Pamlico Sound (PAM-lik-o) in North Carolina, is the largest lagoon along the U.S. East Coast being 80 mi (129 km) long and 15 to 30 mi (24 to 48 km) wide. It is a body of water separated from the Atlantic Ocean by the Outer Banks, a row of low, sandy barrier islands, including Cape Hatteras. The Neuse and Pamlico rivers (the latter is the estuary of the Tar River) flow in from the west. Pamlico Sound is linked on the north with Albemarle Sound through Roanoke Sound and Croatan Sound (passages). Core Sound is the narrow southern end.

Cape Hatteras National Seashore and Cape Lookout National Seashore are located on the barrier islands. Along the coastal areas are numerous waterfowl nesting sites, including Pea Island National Wildlife Refuge and Swanquarter National Wildlife Refuge on the mainland.