Baixa Grande is a tiny settlement in an oasis of Lencois Maranhenses. It sits roughly midway on the route between Atins and Santo Amaro, some 7 km to the southeast of its somewhat larger neighbour, Queimada dos Britos.
Baixa Grande is in the state of Maranhão.
As of 2017 there are 5 families living in Baixa Grande, down from 7 a few years before. Most children leave their families to attend school in Barrreirinhas, and many of these stick to urban life afterwards.
Motorized transport within the national park is prohibited. Only registered residents have a waiver for the use of quad bikes. However, these cannot be used for regular transport of non-residents. I.e. as a tourist your only legal means of access is on foot, or, possibly, riding an animal.
Walk along the quad tracks.
Just suck in the oasis landscape, with the dunes luring in the background.
Apart from your well deserved rest in a hammock, you should ask for a swimmable river or pond. These depend somewhat on the season.
No shops. You'd be lucky(?) to see anything but food with a price attached to it.
Two families in Baixa Grande serve warm meals to hungry trekkers:
Antonio and his wife live only a few hundred metres from the southeastern tip of the oasis. From a distance you will spot a tiny flag on a pole, and also their antenna. Their backyard has a wonderful pond for swimming. A huge helping of chicken, rice and beans with a hammock snooze included is 40 reais.
Don't drink the water from the rivers or ponds. The locals know where to get potable water. If they can drink it, so can you. No need for plastic botlles.
Hammock spaces at the food stations. An overnight should set you back 30 reais.
No cell phone coverage unless you have an external antenna. As of 2017 the operator Vivo had the best coverage.