Mount Apo In the classification system used by local popular mountaineering website PinoyMountaineer.com, the difficulty of the hike is 7 out of 9. Various sights along the trail include Lake Venado, the highest lake in the Philippines, the solfataras and the old crater near its summit. Mount Apo is a headwaters catchment area of several major river systems like Marble River, Matingaw River, connecting with the Kabacan River, part of the Pulangi River, a major tributary of the Mindanao River, the Tudaya Falls, Sibulan River , and Digos River, which flows into Davao Gulf. Mount Apo Mount Apo () and () is
Apo Reef and is about in depth. Likewise, reef limestone and coralline sand on the east and southeastern sides dominantly underlie the area. The main geographical feature of Apo Reef is submerged, but three islands mark it on the surface: the Apo Island, Apo Menor (locally known as "Binangaan") and Cayos del Bajo ("Keys of the bank", locally known as "Tinangkapan"). The islands are uninhabited. Since the declaration of “no-take-zone” policy at Apo Reef Natural Park in 2007, only protected area personnel and members of the Task Force MARLEN (Marine and Apo Reef Law Enforcement for Nature), who are task to implement