Cagayan Valley is a region located in the northeastern part of the Philippines. It is known for its rich agricultural land, producing crops like rice, corn, and tobacco. The region is also home to the Cagayan River, the longest river in the country, which plays a vital role in irrigation and transportation. The valley is surrounded by mountains, including the Sierra Madre range, providing a scenic backdrop. Cagayan Valley is culturally diverse, with various indigenous groups and communities. It is also famous for its historical sites, such as the Callao Cave, which features ancient human remains and artifacts.