The Ikopa River is the second longest waterway in Madagascar and passes through the capital, Antananarivo.^[1] It is the largest tributary of the Betsiboka River. It is formed by the Varahina-North and Varahina-South Rivers.

Its spring, named Varahina, is found in the sub-prefecture of Andramasina at an altitude of 1810 meters.

On this river is situated one of the largest hydroelectrical power stations of Madagascar: the Antelomita Hydroelectric Power Station.