Ciénaga Grande de Santa Marta

The Ciénaga Grande de Santa Marta is the largest of the swampy marshes located in Colombia between the Magdalena River and the Sierra Nevada de Santa Marta. It has an area of 4280 km2 and belongs to the outer delta system of the Madgalena River. It is separated from the Caribbean Sea by a narrow, sandy artificial spit built in the 1950s, on which is situated coastal route 90 from Barranquilla to Santa Marta. The marsh's large lagoon is connected to the Caribbean Sea via a narrow strait located between the town of Pueblo Viejo and the city of Ciénaga.

Source: Wikipedia