By the 1940s and 1950s, logging operations were cutting through Southwest Florida's cypress swamps at an industrial pace. The ancient trees, valued for their rot-resistant wood, were falling by the thousands. In 1954, the Corkscrew Cypress Rookery Association formed with a singular purpose: stop the chainsaws before the last great stand disappeared. The National Audubon Society took over management the following year and began constructing a boardwalk through the swamp in 1955. Over time, nearly the entire wetland was purchased or donated, much of it from Lee Tidewater Cypress Center Co. and Collier Enterprises. Among the donors was Theodore Miller Edison, youngest son of Thomas Edison, whose family had deep ties to Southwest Florida. The result is a sanctuary that exists because people acted just in time -- a few more years of logging and this forest would have been stumps and memory.

A boardwalk stretching over two miles threads through the sanctuary, and walking it feels like passing through a series of distinct ecosystems compressed into a single landscape. Pine flatwoods give way to wet prairie, which dissolves into stands of pond cypress, then deepens into the old-growth bald cypress swamp and finally opens onto freshwater marsh. Each zone has its own character, its own sounds, its own inhabitants. The boardwalk keeps visitors elevated above the waterline, offering views down into the tannin-stained shallows where alligators float motionless and cottonmouth snakes bask on submerged logs. In 2017, Hurricane Irma toppled bald cypress trees across sections of the boardwalk. Most of the damage was repaired, but several small sections remain permanently closed -- the swamp reclaiming what it can.

Corkscrew Swamp Sanctuary is one of the most important breeding sites in North America for the endangered wood stork, a tall wading bird with a bald head and heavy downturned bill that feeds by touch in shallow water. The storks nest in the cypress canopy during the winter dry season, when receding water levels concentrate fish into pools accessible to their specialized feeding technique. They are joined by an extraordinary roster of wading birds: yellow-crowned and black-crowned night herons, tricolored herons, great egrets, and snowy egrets all share the wetland. The painted bunting, a wintering passerine whose plumage looks as if it were assembled from leftover scraps of sunset, appears among the lower vegetation. Limpkins call from the marsh edges with a wailing cry that carries across the water. Barred owls hunt from the cypress canopy, and in summer the elegant swallow-tailed kite soars overhead on long, forked wings.

In 2018, researchers at the sanctuary identified a troubling mystery. Beginning around 2000, the groundwater beneath the park started disappearing during the dry season far faster than it had in the previous four decades of record-keeping. Water levels, measured at Lettuce Lake -- the park's deepest standing water -- had been tracked since 1957. Throughout that period, development had transformed the surrounding landscape: Immokalee Road was built, canals were dug for real estate, agriculture expanded, and neighboring wetlands were paved over. Yet none of those changes had altered the sanctuary's hydrology. Then, without any obvious topographical trigger, the pattern shifted. Wet-season rainfall remained the same, but the dry-season water began draining away rapidly instead of receding slowly as it always had. The cause remains unknown, and the consequences for the wood storks, the cypress trees, and the broader ecosystem of Collier County are still under investigation.

The sanctuary's visitor center is itself a kind of experiment -- a Living Machine demonstration site that uses biological processes to treat wastewater, a fitting introduction to a place where natural systems are the entire point. As a gateway site on the Great Florida Birding Trail, Corkscrew draws birders from around the world who come for the wood storks and stay for the sheer density of wetland life. But the sanctuary's significance extends beyond birding. It is a Ramsar Wetland of International Importance and a National Natural Landmark, designations that acknowledge what becomes obvious the moment you step onto the boardwalk: this is a piece of the original Florida, the subtropical swamp wilderness that existed long before the drainage canals and gated communities, still functioning, still wild, still full of life that depends on water arriving and departing on nature's schedule.