Apo Reef is one of the best tourist spots in Occidental Mindoro. Recognized as the second-largest contiguous reef system in the world next to Great Barrier Reef in Australia, it is being considered as the number one dive site in the Philippines. It is a 34-kilometer reef system divided into north and south lagoon systems by a narrow channel. Jellyfish, turtles, white-tip and black-tip reef sharks, manta rays and vast variety of corals and marine lifeforms one can witness when diving in Apo Reef.

Apo Reef is located in Sablayan, Occidental Mindoro.