Sanibel and Captiva formed as one island about 6,000 years
ago. The first known humans in the area were the Calusa, who arrived about
2,500 years ago. The Calusa were a powerful Indian nation who came to dominate
most of Southwest Florida through trade via their elaborate system of canals
and waterways. Sanibel remained an important Calusa settlement until the
collapse of their empire, soon after the arrival of the Europeans.
In 1765, the first known appearance of a harbor on Sanibel
is shown on a map as Puerto de S
