The Rio Grande de Mindanao, also known as the Mindanao River, is the second longest river in the Philippines after Cagayan River with a length of approximately 373 km. it is the largest river system in the Philippines,.
The Rio Grande de Mindanao, also known as the Mindanao River, is the second longest river in the Philippines after Cagayan River with a length of approximately 373 km. (231 mi) long. It is the largest river system in the Philippines,.