Blue Hole

Blue Hole is Guam's most famous advanced dive site, plunging to 40 meters through a vertical chimney in the limestone reef shelf. Divers descend through a circular opening in the reef top, passing through a shaft that opens into a large cavern with exits to the open ocean wall. The chamber's walls are covered in encrusting sponges and soft corals, while the exits reveal stunning views of the deep blue Pacific. Grey reef sharks, eagle rays, and large tuna are regularly encountered at this world-class site that ranks among the Pacific's most iconic dives.