Mound Key is a state archaeological site containing shell mounds and ridges that rise more than 30 feet above the waters of Estero Bay. The site is believed to have been a ceremonial center for the Calusa Indians who inhabited the coastal waters of southwest Florida. In 1556, the Spanish governor of Florida established a settlement and fort on the island, only to abandon it three years later after a violent clash with the Indians. Mound Key does not have any facilities and is only accessible by boat (and rather tricky to find if you haven’t been there before). There is a .75 mile trail that takes visitors through the island and to the top of the shell mounds. Guided paddle tours are available. Follow the link or call the number provided for more information.
Mound Key is free to visit and explore.