You can’t have failed to notice the 40th anniversary of the Moon landings last month, the only time man has set foot on another world and possibly our greatest achievement.
But there are places on earth so remote, so strange, so alien in fact that a visitor could be forgiven for thinking that they had left the safe confines of Planet Earth...
This natural sinkhole lies 60 miles off the coast of the Central American country of Belize. Formed when sea levels were much lower, it was originally a limestone cave.
As sea levels rose, the cave collapsed, leaving a hole more than 300 metres across and 125 metres deep. Jacques Cousteau declared it one of the best dive sites in the world.
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