Blue Corner is a reef, wall and drift dive site off Koror, Palau, in the Philippine Sea. It is reached by boat, with depths from 7.6 to 30.5 metres. Diving is possible year-round, though strong current is a hazard here. The site lies within the Rock Islands Southern Lagoon, part of Palau's first shark sanctuary. A Koror State Rock Island and Dive Permit is required, costing $50 per person and valid for 10 days. Reef hooks, a technique that originated in Palau, are used at the site. Reef sharks and schooling fish are resident, while hawksbill turtles, humphead wrasse and nudibranchs are occasionally seen, and hammerhead sharks and manta rays are rare.