Following the Karatepe locality, the river turns north and flows through a deep forested valley called Chepinska Bistritsa.

At the town of Velingrad it enters the Chepino Valley, where the river is joined by its largest tributary, the Matnitsa.

At the village of Draginovo it enters the scenic Chepino Gorge between the Rhodope ridges of Alabak to the northwest and Karkaria to the southeast.

[1] Its drainage basin covers a territory of 900 km2 or 1.7% of Maritsa's total[1] and borders the drainage basins of the Stara reka and several small tributaries of the Maritsa to the east, the Vacha to the southeast, the Mesta to the west-southwest and the Yadenitsa to the northwest.

[2] The Septemvri–Dobrinishte narrow-gauge line follows the valley of Chepinska reka in two separate sections — from Varvara to Dolene railway station and from Velingrad to the mouth of the river Ablanitsa.