Darien is a city in and the county seat of McIntosh County, Georgia, United States. It lies on Georgia's coast at the mouth of the Altamaha River, approximately 50 miles south of Savannah, and is part of the Brunswick, Georgia metropolitan statistical area. It is the second-oldest planned city in Georgia and was originally called New Inverness. The population of Darien was 1,460 at the 2020 census, down from 1,975 in 2010.

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.