River of the North-West of Madagascar taking its source in the solid mass of the Tsaratanana. It is thrown in bay of Ampasindava after being joined by another river, Brought back it, in the south of the town of Ambanja.

The name of Sambirano is also used to indicate the whole of the plain where the river is forwarded to the sea. This plain constitutes an extremely fertile basin because profiting from one at the same time hot and wet climate, similar to that of the Eastern littoral of the island, whereas in rule general, the Western littoral of Madagascar is drier.