Geography
Mindanao is the second largest island in the country at 94,630 square kilometers. The island is mountainous, and is home to Mount Apo, the highest mountain in the country. Mindanao is surrounded by seas: the Sulu Sea to the west, the Philippine Sea to the east, and the Celebes Sea to the south. Of all the islands of the Philippines, Mindanao shows the greatest variety of physiographic development. High, rugged, faulted mountains; almost isolated volcanic peaks; high rolling plateaus; and broad, level, swampy plains are found there.

The island group of Mindanao encompasses Mindanao island itself and the Sulu Archipelago to the southwest. The island group is divided into six regions, which are further subdivided into 25 provinces.

 

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