One of the most impressive accomplishments from the Mississippian time period was the construction of Mound Key, a manmade island dating back to 1500 AD built up over a thousand years from discarded shells. It featured a central canal, water-courts, and truncated pyramid shell mounds.
Surrounded by forests of mangrove trees, the shell mounds and ridges of Mound Key rise more than 30 feet above the waters of Estero Bay. Prehistoric Native Americans are credited with creating this island’s complex of mounds with a buildup of seashells, fish bones, and pottery. Mound Key is believed to have been the ceremonial center of the Calusa Indians during the time of Spaniards’ first attempts to colonize Southwest Florida. In 1566, the Spanish governor of Florida set up a settlement on the island with a fort and the first Jesuit mission in the Spanish New World. The settlement was deserted three years later after violent clashes with the Indians.