Tuguegarao is a 1st-class city and capital of the province of Cagayan in the Philippines. It is the regional and institutional center of Cagayan Valley region.The city, on the southern border of the province, is located where the Pinacanauan River empties into the Cagayan River and is surrounded by the Sierra Madre Mountains to the east, Cordillera Mountains to the west, and the Caraballo Mountains to the south.The population of the city as of the May 1, 2010 census is 138,865 people.