The Formation of Sanibel Island

Sanibel Formation

How did Sanibel and Captiva Form

To put it in the simplest of terms Sanibel and Captiva islands were formed about 6,000 years ago from one simple single grain of sand.  It is hard to imagine such a tranquil paradise forming in the most basic of ways.  Dating back to around 3,000 B.C., historians say large amounts of sand and shells flowing from the Caloosahatchee River formed a sand bar off the coast of Florida.  As the sediment grew, an island began to form.  At first, Sanibel and Captiva were joined forming one large island that was shaped by centuries of storm activity.  It is believed that after a very strong tropical storm over 1,000 years ago, the islands were separated, creating a pass between the two, currently known as Blind Pass.  Sanibel Island was formed in an east to west direction, in a crescent moon shape.  This particular shape is beneficial to ensnaring shells and sea life on its beaches, which brought the first signs of life to Sanibel. Also due to this unique shape the sun can be seen both rising and setting over the Gulf of Mexico from our beaches.  Followed by the growth of plants and trees, all kinds of birds and animals made the island their home, due to the abundance of food and shelter. Over time, humans began to inhabit this thriving island, as well.