Because there has been minimal [clarification needed] tourist impact (compared to other, better known locations), Guam has some of the best dive sites in the world. While many of the dive sites can be reached by land, some of the entry points require a long walk over coral or a long surface swim. Many of the dive sites can also be accessed by land through U.S. military bases since they control a great deal of the island.
Piti Bomb Holes has been created into a tourist attraction by allowing tourists to descend into an man-made observatory. Here, they can take in the beauty that has grown in this sinkhole (the name "Bomb Holes" is a misnomer). Divers may dive around this attraction and feed shoals of fish for the amusement of both the tourists inside the subaquatic observatory, and for the divers' themselves.