The Drowning Pool, Waimea Falls Park (Oahu)

Waimea Valley, on O'ahu's North Shore, holds three heiau, including Pu'u o Mahuka, the largest heiau on O'ahu and a luakini temple once used for human sacrifice. Local legend surrounding the pool at the bottom of Waimea Falls tells of an akua, or god, said to periodically claim a human sacrifice from the water — pulling a victim under and holding the body for three days before it's found floating on the surface.