North Carolina's three major topographic regions belong to the Atlantic Coastal Plain, the Piedmont Plateau, and the Appalachian Mountains.
The Outer Banks, narrow islands of shifting sandbars, screen most of the coastal plain from the ocean. Treacherous navigation conditions and numerous shipwrecks have earned the name of "Graveyard of the Atlantic" for the shoal waters off Cape Hatteras, which, like Cape Lookout and Cape Fear, juts out from the banks into the Atlantic. Cape Hatteras Lighthouse is the tallest in the US, rising 208 ft (63 m). The shallow Pamlico and Albemarle sounds and broad salt marshes lying behind the Outer Banks serve not only as valuable habitats for marine life but as further hindrances to water transportation.
On the mainland, the coastal plain extends westward from the sounds for 100 to 140 mi (160–225 km) and upward from sea level to nearly 500 ft (150 m). Near the ocean, the outer coastal plain is very flat and often swampy; this region contains all the natural lakes in North Carolina, the largest being Lake Mattamuskeet (67 sq mi/174 sq km), followed by lakes Phelps and Waccamaw. The inner coastal plain is more elevated and better drained. Infertile sand hills mark its southwestern section, but the rest of the region constitutes the state's principal farming country.
The Piedmont is a rolling plateau of red clay soil roughly 150 mi (240 km) wide, rising from 30 to 600 ft (90–180 m) in the east to 1,500 ft (460 m) in the west. The fall line, a sudden change in elevation, separates the piedmont from the coastal plain and produces numerous rapids in the rivers that flow between the regions.
The Blue Ridge, a steep escarpment that parallels the Tennessee border, divides the piedmont from North Carolina's westernmost region, containing the highest and most rugged portion of the Appalachian chain. The two major ranges are the Blue Ridge itself, which averages 3,000–4,000 ft high (900–1,200 m), and the Great Smoky Mountains, which have 43 peaks higher than 6,000 ft (1,800 m). Several smaller chains intersect these two ranges; one of them, the Black Mountains, contains Mt. Mitchell, at 6,684 ft (2,039 m) the tallest peak east of the Mississippi River.
No single river basin dominates North Carolina. The Hiwassee, Little Tennessee, French Broad, Watauga, and New rivers flow from the mountains westward to the Mississippi River system. East of the Blue Ridge, the Chowan, Roanoke, Tar, Neuse, Cape Fear, Yadkin, and Catawba drain the piedmont and coastal plain. The largest artificial lakes are Lake Norman on the Catawba, Lake Gaston on the Roanoke, and High Rock Lake on the Yadkin.