Blue Holes

You drop through one of four circular openings in the reef top, and the world changes. The walls widen as you descend, the blue deepens, and shafts of sunlight pour through the holes above you like spotlights in an empty theatre. Far below, the shafts angle across a single shared cavern; ahead, an exit opens through the reef wall into blue water.

Blue Holes, on the Ngemelis reef plateau in Palau, begins as four vertical sinkholes, their mouths ten to fifteen metres wide and the shallowest rim barely a metre beneath the surface. Below, they join through short swim-throughs into one cavern whose floor lies at roughly forty metres, and daylight follows you the whole way down, falling in blue columns divers call Jesus light. The ceiling has its own residents: blacktip grouper, Collin's angelfish, bluefin trevally and juvenile triggerfish hold station among the openings. It is an overhead environment, dived with a local guide along a route matched to training and the day's water. When current and ability allow, guides run the classic line, entering through the Blue Holes and exiting onto Blue Corner, two of the Pacific's most celebrated dives joined into one.