[citation needed] The Chandragiri or Perumpuzha River is considered the traditional boundary between the Tulu Nadu and Malayalam regions of Kerala.

In 16th-century Portuguese geographies, the Chandragiri River is called the "Rio Cangerecora", and identified as the boundary between the "province of Canará" (Kannada-speaking coastal south Karnataka, vassal of "Bisnaga", Vijayanagara Empire) and the independent kingdoms of "Malabar" (Kerala).

The Chandragiri River originates from the northern slopes of the Greater Talacauvery National Park in the Western Ghats at the Kodagu district, Karnataka.

Chandragiri then enters Kerala and flows through several hilly towns in the eastern part of the Kasaragod district – Panjikkal, Kottyadi, Adhur, Poovadka, Kottamkuzhy, Bethurpuzha, Kundamkuzhy, Kolathur, Muliyar and Bovikanam.

Then the river enters into the Malabar plains where it flows through Thekkil, Chengala, Chattanchal, Perumbala, Chemnad and Kasaragod.