The Blue Hole, one of Guam’s most popular divesites, is a natural limestone shaft extending down into the reef. Soft and hard corals, sea whips, fish and eels can be seen inside the shaft.
The upper opening is at 60 feet. From there, the shaft drops to 300+ feet. Gliding down the awe-inspiring shaft can get even the most experienced diver’s adrenaline up, so watch your descent rate and depth carefully.
The first opportunity to exit the shaft is at 127 feet. It's not uncommon to see large pelagic fish outside the opening, and as you follow the wall on the outside of the Blue Hole you probably will see more.
Once out of the shaft, ascend to about 80 feet and follow the contour of the wall for a while. Then ascend to the 60’ reef flat where there is a variety of hand-fed fish and several large boulders covered with interesting corals and algae. Watch for large trigger fish and lots of schooling fish.
CAUTION: Many divers descend through the opening in the top and exit out the "window". THIS IS A DEEP DIVE so watch your air carefully. Many divers have been treated at the chamber because of poor dive management. Pay attention.