This key, only accessible by boat, encompasses a 280-acre island of virgin tropical forest and is home to roughly a zillion jillion mosquitoes. The official attraction is the 1919 Matheson House , with its windmill and cistern; the real draw is a nice sense of shipwrecked isolation. Guided walking tours (1¼ hours) are given at 10am and 2pm Friday to Sunday. You’ll have to get here via Robbie’s Marina ; boats depart for tours to here and Indian Key .
Strangler figs, mastic, gumbo-limbo, poisonwood and lignum vitae trees form a dark canopy that feels more South Pacific than South Florida.