The Blue Hole

The Blue Hole dive location is located off Guam's western coast. It's been called "Guam's iconic natural feature dive," "the most sought dive site on Guam," and "one of Guam's most popular dive sites," among other things. It's near the entrance of Apra Harbor in northern Agat Bay. Despite its proximity to the Orote Peninsula's southern coast, sheer cliffs make it only possible to dive from a boat, which departs from Cabras Marina in Apra Harbor, about 20 minutes away. The underwater sinkhole's top starts at 60 feet (18 meters) and lowers to about 300 feet (91 m).

However, because the sinkhole is near a wall and has an opening that enables egress at roughly 130 feet (40 meters), it may be considered an advanced recreational dive, depending on the certifying body. To divers inside the sinkhole, the aperture appears to be in the shape of a heart. While the dive boat is connected up to a mooring buoy for entry, exit usually entails deploying a surface marker buoy in an east-to-west current and picking up in the open ocean.

This limestone shaft, located on the southern coast of the Orote Peninsula, entraps divers as they freefall through limestone walls and moray eels. A passageway around 125 feet down permits them to gently climb using another path—despite the fact that the dip beneath their flippers is far deeper than diving safety allows.