The Savannah River is a major river in the Southeastern United States, forming most of the border between South Carolina and Georgia. Two tributaries of the Savannah, the Tugaloo River and the Chattooga River, form the northernmost part of the state border. The Savannah River drainage basin extends into the southeastern side of the Appalachian Mountains just inside North Carolina, bounded by the Eastern Continental Divide. The river is around 301 miles (484 km) long. The Savannah was formed by the confluence of the Tugaloo River and the Seneca River. Today this confluence is part of Lake Hartwell. The Tallulah Gorge is located on the Tallulah River, a tributary of the Tugaloo River that forms the northwest branch of the Savannah River.

South Carolina is a state in the coastal Southeastern region of the United States. It borders North Carolina to the north, the Atlantic Ocean to the southeast, and Georgia to the southwest across the Savannah River. Along with North Carolina, it makes up the Carolinas region of the East Coast. South Carolina is the 40th-largest and 23rd-most populous U.S. state with a recorded population of 5,118,425 according to the 2020 census. In 2019, its GDP was $213.45 billion. South Carolina is composed of 46 counties. The capital is Columbia with a population of 136,632 in 2020; while its most populous city is Charleston with a 2020 population of 150,227. The Greenville-Spartanburg-Anderson, SC Combined Statistical Area is the most populous combined metropolitan area in the state, with an estimated 2023 population of 1,590,636.