Apo Reef is a coral reef system in the Philippines situated on the western waters of Occidental Mindoro province in the Mindoro Strait. Encompassing 34km2, it is considered the world's second-largest contiguous coral reef system, and is the largest in the country. The reef and its surrounding waters are protected areas in the country administered as the Apo Reef Natural Park (ARNP). It is one of the best known and most popular dive sites in the country. It is listed in the tentative list for UNESCO World Heritage Sites.
