At first glance Lençóis Maranhenses looks like an archetypal desert. In fact it isn't actually a desert just like the Tottori Sand Dunes aren’t. Lying just outside the Amazon basin, the region is subject to a regular rain season during the beginning of the year. The rain water accumulates in the valleys in between sand dunes and forms clear blue and green lagoons that reach their fullest between July and September. The area is also surprisingly home to a variety of fish which, despite the almost complete disappearance of the lagoons during the dry season, have their eggs brought from the sea by birds. Mangroves, deserted beaches, buritis - a graceful kind of palm tree - and the Preguiças River help compose the park's diversity.
Lençóis Maranhenses has been formed over thousands of years, as the sand from riverbeds is deposited at the mouth of the rivers and brought back to the continent by winds and sea currents.
The dunes advance as far as 31 miles into the continent and stretch along 27 miles of coastline, mostly deserted beaches. Some of the lagoons at Lençóis Maranhenses National Park are huge. Lagoa Bonita and Lagoa Azul are near the town of Barreirinhas. Lagoa Tropical, also worth a visit, is closer to the village of Atins. Lagoa da Gaivota (Seagull Lagoon), one of the park's largest and most beautiful, is near Santo Amaro do Maranhão, a village located about 60 miles from Barreirinhas.
The best time to visit the park is roughly from May to September, when it's sunny, yet the lagoons are still full.
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