The Mangoro River is the largest river on the east coast of Madagascar by basin size and water volume, and is 300 km in length.

[3] The Mangoro begins northeast of the town of Anjozorobe in the Analamanga region, at approximately 1,100 meters.

[4][1] Its mouth is at the Indian Ocean near the town of Ambodiharina.

Owing to its many tributaries, the Mangoro maintains a high flow year round, making it an ideal river for rafting.

[5] As of 2012, the Sherritt International Corporation planned to use the Mangoro River as a source of water for a slurry pipeline carrying ore for the Ambatovy project mines, raising environmental concerns.