Demere Key is an archaeological site west of Pine Island, Florida. On June 13, 1972, it was added to the U.S. National Register of Historic Places.The island is named for its early owner, Lewis Deméré (1813 - About 1880), who was born at St. Simons Island, Georgia. He and his wife, Virginia Clancy Barnard Deméré (1821–1900) and son, Raymond Barnard Deméré (1843–1905) lived on the island until about 1880.