Turtle Canyon

Sitting roughly 1.5 to 2.5 miles off Oahu's south shore, this open-water reef requires a 10-to-20-minute boat ride from Waikiki or nearby harbors rather than a swim from the beach.

Beneath the surface, clear water covers rock formations and coral patches where small fish strip away algae and parasites. That steady routine makes it one of the island's most dependable locations for seeing wild sea turtles in the open ocean, flanked by schools of wrasse, tangs, and butterflyfish.