The Suwannee River is a river that runs through south Georgia southward into Florida in the Southern United States. It is a wild blackwater river, about 246 miles (396 km) long. The Suwannee River is the site of the prehistoric Suwanee Straits that separated the Florida peninsula from the Florida panhandle and the rest of the continent.

A blackwater river is a type of river with a slow-moving channel flowing through forested swamps or wetlands. Most major blackwater rivers are in the Amazon Basin and the Southern United States. The term is used in fluvial studies, geology, geography, ecology, and biology. Not all dark rivers are blackwater in that technical sense. Some rivers in temperate regions, which drain or flow through areas of dark black loam, are simply black due to the color of the soil; these rivers are black mud rivers. There are also black mud estuaries.