Everglades National Park

No earlier national park had been created for a landscape most Americans considered worthless. The Everglades offered no towering peaks or waterfalls — just a slow-moving sheet of water, sawgrass, and mangrove draining south through Florida — and for decades the federal government's policy toward it was to drain it, not protect it. That changed as biologists documented the collapse of wading-bird populations and the strange, singular ecology of a river 50 miles wide and six inches deep. In 1947, after a 20-year campaign led largely by conservationist Ernest F. Coe, Congress and President Harry Truman established Everglades National Park, the first major American national park set aside explicitly to preserve an ecosystem rather than a scenic spectacle.

The Everglades had already functioned as a refuge once before the park existed: Seminole people retreated deep into its sawgrass and hardwood hammocks during the wars of the 1830s and 1840s, using terrain the U.S. Army found nearly impossible to fight through, and their descendants, the Seminole Tribe of Florida and the Miccosukee Tribe, still live on reservation land bordering and partly within the park's original boundaries today. Protection never stopped the drainage fights. Decades of canals, levees, and agricultural diversion upstream cut the water reaching the park by more than half, and since 2000 state and federal agencies have spent billions of dollars trying to undo damage done both before and after the park was created.

The park now protects the largest subtropical wilderness in the United States and the only place on Earth where alligators and American crocodiles share the same waters. It remains one of the most threatened parks in the national park system, caught between the farms and growing cities of South Florida that compete for the same water the fragile ecosystem depends on to survive.