The Simuay River is a river in the Philippines with its source at
Lanao del Sur
Lanao del Sur ( tl, Timog Lanao; Maranao and ilp, Pagabagatan Ranao), officially the Province of Lanao del Sur, is a province in the Philippines located in the Bangsamoro Autonomous Region in Muslim Mindanao (BARMM). The capital is the city o ...
in the
Piapayungan range, and its mouth at is at
Illana Bay
Illana Bay, also known as the Iranun Bay, is a large bay of the Moro Gulf, off the southwestern coast of Mindanao island in the Philippines.
Illana Bay and Moro Gulf form part of the Celebes Sea
The Celebes Sea, (; ms, Laut Sulawesi, id, L ...
through the
Mindanao River
The Rio Grande de Mindanao, also known as the Mindanao River, is the second-largest river system in the Philippines. Located on the southern island of Mindanao, with a total drainage area of , draining the majority of the central and eastern po ...
.
Rivers of the Philippines
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