is a national park with sand dunes in the northeast of Brazil. It is not quite a typical "beach". But it's rather a large desert near the Atlantic Ocean. Unlike classic deserts, it has also hundreds of small lakes, - some with clear azure water, while some others are more like a swamp. Along the edges of the Park, you can also find many dunes overgrown with trees and other lush vegetation. This is not the best place, if you need just to swim and to sunbathe. On the other hand, this is a totally unique spot being a desert with great opportunities for a beach holiday. Shore and seabed: sand. 
In the southwest of National Park, there is Santo Amaro
town with good choice of hotels. Rooms' fares range from US$30 to US$600 per night.
It makes sense to choose options located near the entrance to the Park (Parque Nacional dos Lençóis Maranhenses
), since the town itself is not very interesting. However, if you plan to take 4WD tours, then it will be better to take room in the city center. Most of cafes are also located in the center. In any case, the town is small enough. So you can just walk everywhere. Find hotels in Lencois Maranhenses
How to get there 
Fly to Sao Luis international airport (SLZ)
. Next take a bus or hire a taxi. Find flights to Lencois Maranhenses
When to go 
The best time for a beach holiday in Sao Luis region is a dry season from June to December.
Water temperature, C
Wind speed, meter/sec