Mindanao /mɪndəˈnaʊ/ min-də-now is the second largest and easternmost island in the Philippines. It is also the name of one of the three island groups in the country, which consists of the island of Mindanao and smaller surrounding islands. The other two are Luzon and the Visayas. The island of Mindanao is called The Land of Promise. Mindanao is the only area of the Philippines with a significant Muslim presence.

Reference: http://en.wikipedia.org/wiki/Mindanao