Swamps are found in wetlands (places that are permanently waterlogged), such as the delta of a river. Because of the waterlogged conditions, the plants that grow in swamps are specially adapted. Swamps have visible standing water and are dominated by trees (compared with marsh, dominated by grasses and a bog, which does not appear waterlogged).

The Okavango Delta and Swamp, Botswana is one of the world's largest swamps. The Okavango River, which originates in the plateau of southeastern Angola, provides an intermittent flow of water as the river enters the delta area from the northwest. Because this delta is situated in a desert climate, Earth scientists have called this site one of the most ecologically sensitive areas on the planet. There is constant competition among would-be users of the land, including farmers, cattle ranchers, and those who would establish a natural game preserve. Hot, humid conditions make this area an ideal habitat for the tsetse fly, a known carrier of African sleeping sickness.

The Everglades of Florida is perhaps the world's best-known swamp. It is a national park.