Cordillera Central (Luzon) Sierra Madre Mountains, the longest mountain range in the country, through the Caraballo Mountains in Nueva Vizcaya province. During Spanish colonial period, the whole range was called "Nueva Provincia", (New Province). The Cordillera Central is the highest mountain range in the Philippines. It comprises about 1/6 of the whole Luzon island with a total area of . The highest mountain in the range, Mount Pulag, is also the highest mountain on Luzon Island at . It is officially the third highest mountain in the country after Mount Dulang-dulang and Mount Apo on Mindanao Island, the second largest island of the
Mount Apo in Mt. Apo Natural Park. This waterfall flows into the Sibulan River, which flows to the Davao Gulf. Grasslands – The grasslands are characterized by the dominance of Cogon grass ("Imperata cylindrica") and "Saccharum spontaneum". Other grasses and ferns also thrive, especially along banks of creeks, streams, and rivers and on steep slopes. The Mt. Apo 1 and Mt. Apo 2 geothermal plants, each possess a rated capacity of 54.24 megawatts. Owned and operated by Energy Development Corporation (EDC) the power plants were commissioned in February 1997 (Mt. Apo 1) and June 1999 (Mt. Apo 2) respectively, under a build-operate