Georgia’s Okefenokee Swamp is the latest wild wonder of the USA to make UNESCO’s hallowed World Heritage Site list. It joins the Grand Canyon, Sequoia, Everglades, and Yellowstone national Parks on the same list, and reflects the stunning biodiversity of American “blackwater” swamps. Most of the Okefenokee Swamp is included in the 403,000-acre (163,000 hectare) Okefenokee National Wildlife Refuge, the most-visited NWR east of the Mississippi. The federal government acquired most of the swamp for refuge purposes in 1936, and designated it an NWR a year later. Okefenokee Swamp is the largest, lowland, freshwater peatland in the subtropical zone worldwide, and one of the largest and most intact ecosystems within the North American Coastal Plain global biodiversity hotspot.