Gulf of Urabá
The Atrato River () is a river of northwestern Colombia. It rises in the slopes of the Western Cordillera and flows almost due north to the Gulf of Urabá (or Gulf of Darién), where it forms a large, swampy delta. Its course crosses the Chocó Department, forming that department's border with neighboring Antioquia in two places. Its total length is about , and it is navigable as far as Quibdó (400 km / 250 mi), the capital of the department.