Lençóis Maranhenses National Park

National park in Maranhão, Brazil

Lençóis Maranhenses National Park (Parque Nacional dos Lençóis Maranhenses) is a national park in Maranhão state in northeastern Brazil, just east of the Baía de São José. Protected on June 2, 1981, the 155,000 ha (380,000-acre) park includes 70 km (43 mi) of coastline, and an interior composed of rolling sand dunes. During the rainy season, the valleys among the dunes fill with freshwater lagoons, prevented from draining by the impermeable rock beneath.

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