Corkscrew Swamp Sanctuary, Nature reserve and National Natural Landmark in Collier County, United States.

Corkscrew Swamp Sanctuary is a National Audubon Society reserve in Collier County, Florida, north of Naples and east of Bonita Springs. A 2.25-mile wooden boardwalk with dark railings runs low over marsh and wet prairie, past stands of pond cypress and bald cypress, toward a grove of bare trees. The sanctuary protects one of the largest remaining stands of old-growth bald and pond cypress in North America.

The Corkscrew Cypress Rookery Association formed in 1954 to protect the cypress stands from logging. The National Audubon Society took over management and began building the first boardwalk in 1955. Nearly 45 km2 of wetland was purchased or donated, much of it by Lee Tidewater Cypress Center Co. and Collier Enterprises, with funding from Theodore Miller Edison, Thomas Edison's youngest son.

The sanctuary is a gateway site on the Great Florida Birding Trail. It was an important breeding area for the endangered wood stork, and wintering painted buntings are among the passerines recorded here. Wading birds such as the yellow-crowned night heron, tricolored heron, great egret and snowy egret can be seen in the wetlands, along with limpkin, barred owl and, in summer, swallow-tailed kite.

The sanctuary lies north of Naples and east of Bonita Springs in Collier County, reached via Immokalee Road. The 2.25-mile boardwalk crosses pine flatwoods, wet prairie, cypress stands and marsh; several short sections were permanently closed after Hurricane Irma in 2017. Bring insect repellent in warmer months and wear shoes suited to wooden planks.

The sanctuary was an important breeding area for the endangered wood stork, and it also hosts wintering painted buntings. American alligators and cottonmouth snakes live in its wetlands. The visitor center has a Living Machine demonstration site and the Spurlino Foundation Discovery Center, which opened in 2026.