Where is Lencois Maranhenses, and the way in from Sao Luis

Where is Lencois Maranhenses, in plain terms? It is a national park on the Atlantic coast of Maranhao, the state that forms the north-eastern shoulder of Brazil where the Amazon gives way to the dry north-east. A NASA caption places the dune field on the country's north coast, about 700 km east of the mouth of the Amazon.⁸ Barreirinhas, Santo Amaro do Maranhao and Primeira Cruz, 3 municipalities in all, share the park between them.¹

On a road map the park is a pale wedge between Sao Luis, the state capital, and the delta of the Parnaiba river. The state tourism office describes white dunes reaching about 50 km inland from the sea and running along more than 70 km of empty beach.⁹ ICMBio, the federal agency that manages it, gives the park an area of 156,608.16 hectares, with 2/3 of it covered by dunes and the lagoons between them.¹⁰

That position explains the landscape. NASA's Earth Observatory notes that the dune field sits where three Brazilian biomes meet, with Amazon rainforest to the west, Cerrado savanna to the south and the thorny Caatinga to the east.¹¹ You feel the mix on the drive in, as palm groves, mangroves and scrub take turns outside the window, and the sand appears only at the very end, often all at once.

Barreirinhas, on the Preguicas river, is the main base for the park, and the classic Lagoa Azul and Lagoa Bonita trips start there.¹³ The state tourism office lists the route from Sao Luis as the BR 135 to Bacabeira, the BR 402 to Rosario, then the MA 110, MA 226 and MA 225 into town, and reckons on 3 hours by car.³ It is the gateway easiest to reach from the capital, with the widest choice of beds.¹⁸

There are several practical ways to cover that road. Buses leave the Sao Luis bus terminal every day.³ A shared transfer collects you and drops you at your lodging, from $47. A private car for your own group runs 4 to 4.5 hours each way. Or you drive yourself, which gives the most freedom between town and coast but stops at the park boundary, as the next sections explain.

If you are planning a Lencois Maranhenses tour from Sao Luis in a single push, be realistic about the clock. With 4.5 hours on the minibus and the morning departure window, you reach Barreirinhas around midday at the earliest, and the full-day lagoon tours leave in the morning. The simple plan is to sleep in Barreirinhas and book the lagoon day for the next morning, which leaves the arrival afternoon for a walk along the river and an early night.

Atins is a fishing village between the dunes of the Grandes Lencois, the beach and the Preguicas river, close to the Azul and Bonita lagoons.⁵ The park plan describes it as a former village of traditional fishermen that has become an important place for kitesurfing.¹⁶ It has no road from Sao Luis of its own: you reach it from Barreirinhas, by boat down the river or by off-road vehicle across the sand.

The boat is the more scenic way. The state tourism office points out that arriving along the Preguicas lets you explore the creeks and meet the people who live on them, without hurry.⁴² A shared speedboat transfer takes 1.5 hours, from $51. On the way the river passes Mandacaru, whose 54 m lighthouse gives a sweeping view of the dunes and the river from the top.²² The climb is steep, so save some energy for it.

Across the water lies Cabure, a beach the park plan lists among the region's attractions beyond the park, along with the Pequenos Lencois and the river itself.²¹ If you choose Atins as your base, you can arrange the boat and lagoon trips from the village, but check the last river crossing of the day before you commit, since there is no quick way back to Barreirinhas once it has gone.

Your own car gets you to the gateway towns, not into the park. ICMBio allows only vehicles, drivers and guides accredited through a public call to take visitors inside.⁷ Private cars, motorbikes, buggies, quad bikes and UTVs that the agency has not authorised may not enter.⁴⁵ The state tourism office sums it up from the visitor's side: you go in by 4x4 with a town agency, which leaves you at the edge of the dunes.⁴⁶

From that drop-off point you continue on foot. The park plan describes visitors walking over the dunes from the support point to a sequence of lagoons.⁴⁷ That is why every tour here is partly a hike, and why the state advises good fitness, sunscreen, light clothes and steady drinking.³⁵ In many places the dunes give no landmark and no shade, so going with a guide is safety, not a formality.

Phones are not much help either. ICMBio warns that it is very easy to get lost in the dune field and that much of it has no mobile coverage.³⁶ Book the lagoon day through an accredited operator, keep your guide in sight, and treat the map on this page as a way to understand the distances rather than a route to follow alone. The park is open to visitors all year round, so the journey itself is the only thing you really need to plan around.³⁷