The Altamaha River is a major river in the U.S. state of Georgia. It flows generally eastward for 137 miles (220 km) from its origin at the confluence of the Oconee River and Ocmulgee River towards the Atlantic Ocean, where it empties into the ocean near Brunswick, Georgia. No dams are directly on the Altamaha, though some are on the Oconee and the Ocmulgee. Including its tributaries, the Altamaha River's drainage basin is about 14,000 square miles (36,000 km2) in size, qualifying it among the larger river basins of the US Atlantic coast.

Brunswick is a city in and the county seat of Glynn County in the U.S. state of Georgia. As the primary urban and economic center of the lower southeast portion of Georgia, it is the second-largest urban area on the Georgia coastline after Savannah and contains the Brunswick Old Town Historic District. At the 2020 U.S. census, the population of the city proper was 15,210; the Brunswick metropolitan area's population as of 2020 was 113,495.