Covering over 400,000 acres in southeast Georgia, Okefenokee National Wildlife Refuge is one of the largest intact freshwater ecosystems in the world. The swamp is home to over 600 plant species and provides habitat for an amazing variety of amphibians and birds. You can also see black bears and of course, American alligators. Here’s one swimming towards a rainbow. Photo by Sarah Wyatt, U.S. Fish and Wildlife Service.