Piranhas River

{{Short description|River in northeastern Brazil}}

{{about||other Brazilian rivers}}

{{Infobox river

| name = Piranhas River

| native_name = {{native name|pt|Rio Piranhas-Açu}}

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| image = Rio Piranhas-Açu - RN.jpg

| image_size = 240px

| image_caption = The Piranhas River in Rio Grande do Norte state

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| pushpin_map = Brazil

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| subdivision_type1 = Country

| subdivision_name1 = Brazil

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| length = {{convert|447|km|mi|abbr=on}}

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| source1 = Paraíba state

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| mouth = Rio Grande do Norte state

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}}{{Expand Portuguese|topic=geo|date=June 2022}}

The Piranhas River ({{langx|pt|Rio Piranhas-Açu}}), also known as the Açu River, is a river of northeastern Brazil.{{Cite web |title=GHAASBasin369 - Jardim de Piranhas |url=https://archive.wikiwix.com/cache/index2.php?url=http://www.grdc.sr.unh.edu/html/Polygons/P3650750.html#federation=archive.wikiwix.com |access-date=2022-06-15 |website=archive.wikiwix.com}} It originates in southeastern Paraíba state, near the border with Ceará, and flows north-northeast through Paraíba and Rio Grande do Norte states to empty into the Atlantic Ocean near Macau. Its chief tributary is the Seridó, which originates in the Borborema Plateau of central Paraíba and flows northwest to meet the Piranhas.