Cagayan Valley: The Deep North

Cagayan Valley (Region II) is the northeastern region of Luzon, heavily agricultural and defined by the Cagayan River, the country’s longest river system. It comprises the mainland provinces of Cagayan, Isabela, Nueva Vizcaya, and Quirino, plus the northern island province of Batanes. It is geographically isolated by the Sierra Madre to the east and the Cordillera Central to the west. Reference stub.