It has an estimated drainage area of 5,125 square kilometres (1,979 sq mi) and a length of 179 kilometres (111 mi) from its source near Mount Data in Benguet province.

Bernardo Lago arrived on the town of Pidigan, where he built a church and a rectory atop a hill near the river, marking the official start of Catholicism in Abra.

[4] The Abra originates in the southern section of Mount Data.

It descends westward to Cervantes, Ilocos Sur, and flows into Abra.

At a point near the municipality of Dolores, it is joined by the Tineg River, which originates in the uplands of Abra.