The state s coastline along the Atlantic Ocean is about 100 miles long. However, when all the river estuaries, bays, and islands are included, the coastline is 2,344 miles long. Saltwater tidal marshes are found in most river estuaries. Just off the mainland, separated from it by a narrow and sheltered waterway, lies a chain of low islands. The islands, which continue along the coast of South Carolina, are called the Sea Islands.
Sandy beaches fringe the seaward sides of many of the islands.
Several of these islands are now developed, but two, Sapelo and Cumberland, are mostly owned by the state and largely remain in a natural condition. Along the Coastal Plain and in much of the Piedmont, summers are generally hot, and winters are mild. The relative humidity is generally high throughout the year. In the mountains, in northern Georgia, cooler conditions prevail. The average January temperature on the Coastal Plain and the Piedmont ranges from about 44 in the north to about 54 in the south.