Okefenokee Swamp
The Okefenokee Swamp is a shallow, 438,000-acre (177,000 ha), peat-filled wetland straddling the Georgia–Florida state border in the United States. A majority of the swamp is protected by the Okefenokee National Wildlife Refuge and the Okefenokee Wilderness and was designated a National Natural Landmark in 1974.