The Timucuan Ecological and Historic Preserve covers 46,000 acres of coastal wetlands, salt marshes, tidal creeks, and barrier islands on both sides of the St. Johns River mouth, making it one of the largest undeveloped estuaries on the US Atlantic coast. The preserve protects both the natural ecosystem — which supports manatees, bottlenose dolphins, bald eagles, wood storks, and a huge variety of shorebirds — and multiple historical sites from the Spanish colonial and Civil War periods.
The Kingsley Plantation, on Fort George Island, is the most accessible historical site within the preserve — a well-preserved early 19th-century plantation with the slave cabins still standing, which give a direct and sobering picture of the plantation system. The Ribault Club, nearby, is an extraordinary 1920s Spanish Revival building on the waterfront. Kayaking through the tidal creeks of the preserve is one of the best outdoor activities in the Jacksonville area.