Blue Hole (Big Pine Key)
The Blue Hole is an attraction on the island of Big Pine Key in the Florida Keys. It is an abandoned rock quarry that was used for nearby road fills and Henry Flagler's Overseas Railroad. The water it contains is mostly fresh and is used by various wildlife in the area, such as birds, snakes, alligators, key deer and green iguanas. It is part of the National Key Deer Refuge.
Blue Hole (Red Sea)
However, the Sinai Peninsula was occupied by Israel during the Six-Day War of 1967 (with Israel occupying the territory until 1982). The first people to dive the hole with modern scuba diving equipment were Israeli divers led by Alex Shell, who noticed the underwater arch in 1968. By the time Israel handed the Sinai Peninsula back to Egypt in 1982, the Blue Hole had developed a reputation as a diving site amongst the international scuba diving community.