Lencois Maranhenses a desert with lagoons

Located in the State of Maranhão, on the north shore of Brazil, the Lençóis Maranhenses National Park is an area of about 300 square kilometers (155,000 ha) of blinding white dunes and deep blue lagoons, forming one of the most beautiful and unique places in the world. The dunes invade the continent over 50km (31 miles) from the cost, creating a landscape that reminds a white bed sheet, when seen from above. Lençóis Maranhenses looks like an archetypal desert. In fact it isn't actually a desert. Lying just outside the Amazon basin, the region is subject to a regular rain season during the beginning of the year. The rains cause a peculiar phenomenon: fresh water collects in the valleys between sand dunes, spotting the desert with 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. link