2. Samaesan Hole, Thailand
Located in Thailand’s Samaesan Bay, the Samaesan Hole reaches depths of almost 300 feet. While it is a popular spot for experienced divers, many have run into trouble there. A former military munitions dump, there is believed to be unexploded ordinance in among the depths. As if that’s not enough to dissuade you, strong currents have frequently been known to take divers far away from their courses.
