Sanibel Island is an island located on the Gulf coast of Florida, just offshore of Fort Myers. In 2000, it had an estimated population of 6,064 people. Located within Lee County, Sanibel is a barrier island – a collection of sand on the leeward side of the Gulf Stream from the more solid coral-rock of Pine Island. The city of Sanibel incorporates the entire island, with most of the city proper at the east end of the island.