The Seven Wonders of the World. 10 Most Fascinating Holes on Earth. Great Blue Hole (Belize) Located in Belize's Barrier Reef Reserve System, the "Great Blue Hole" is about 60 miles away from Belize City and is believed to be the world's largest sea-hole.
It's 125 meters deep and 300 meters wide. Product Photography Tips. Trail Cooking & The Outdoors.