Cagayan River
longest and largest river in the Philippines
The Cagayan River, also known as the Río Grande de Cagayán, is the longest river and the largest river by discharge volume of water in the Philippines. It has a total length of approximately 505 kilometres (314 mi) and a drainage basin covering 27,753 square kilometres (10,715 sq mi). It is located in the Cagayan Valley region in northeastern part of Luzon Island and traverses the provinces of Nueva Vizcaya, Quirino, Isabela and Cagayan; it also flows through the only Central Luzon province of Aurora.
Topography
The river's headwaters are at the Caraballo Mountains of the Central Luzon at an elevation of approximately 1,524 metres (5,000 ft). The river flows north for some 505 kilometres (314 mi) to its mouth at the Babuyan Channel near the town of Aparri, Cagayan. The river drops rapidly to 91 metres (299 ft) above sea level some 227 kilometres (141 mi) from the river mouth. Its principal tributaries are the Pinacanauan, Chico, Siffu, Mallig, Magat and Ilagan Rivers.
Magat River, is the largest tributary with an estimated annual discharge of 9,808 million cubic meters. It lies in the southwestern portion of the basin, stretching approximately 150 kilometres (93 mi) from Nueva Vizcaya down to its confluence with Cagayan River about 55 kilometres (34 mi) from the river mouth.
Both Magat and Chico Rivers have extensive drainage areas which comprise about 1/3 of the whole basin.
The public source identifies “Cagayan River” as longest and largest river in the Philippines. This brief keeps that definition visible, then builds a research path around Cagayan, River and longest.
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Maps, plans, fabric surveys and administrative records can establish how the site’s name, extent and function changed over time. The source revision retrieved here is dated Aug 2, 2026. The linked authority identifier is Q545808. VIAF identifies the subject as 315529931. Authority coordinates are 16.186, 121.144. 2 of 3 selected statements include explicit references; 2 carry qualifiers and 0 use preferred rank.
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This entry incorporates text from “Cagayan River” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.