Lencois Maranhenses National Park

The approach to Lencois Maranhenses from the park entrance at Barreirinhas takes you through a transition from scrubland to the dune field over about 30 minutes by 4WD vehicle, and the transition itself is part of the experience: the trees thin, the ground turns sandy, and then suddenly you are among dunes that look like they belong in the Sahara, except that between them are electric-blue lagoons filled with freshwater fish. The combination of desert and wetland is the park's central surprise, and it takes the first hour of walking through the dunes to adjust to the visual incongruity.

The lagoons (called lagoas) form during the rainy season from January to June when rainfall percolates through the sand and is caught by the impermeable rock layer beneath, preventing drainage. By July the lagoas are at their fullest and most vivid: the blue is intensified by the white quartz sand that surrounds them, and at certain times of day the colour contrast between water and dune is almost too deliberate to seem natural. By September the lagoas begin to shrink and some disappear entirely, leaving white hollows in the sand.

The scale of the dunes is not apparent from the edge. From a distance the dune field looks like a series of gentle white hills; closer, individual dunes reach 30 to 40 metres in height and the crests are sharp and windswept. Walking to the top of a dune and looking back over the field: dozens of white crests stretching to the horizon, is one of the most disorienting experiences in Brazilian nature, as the mind tries to reconcile the presence of a desert with the tropical forest visible on the horizon.

The park is not a desert in the ecological sense: the surrounding Atlantic Forest and the temporary wetland conditions support a surprising diversity of species, including four listed as endangered. The lagoas contain fish species that have evolved specifically to survive in these isolated, seasonal bodies of water. Birdlife is rich, particularly during the wet season migration periods. The park's 70-kilometre coastline adds a further dimension: the dunes meet the sea at some points, and the tidal exchange creates a different ecological zone at the shoreline.

Access to the interior lagoons requires a local guide and typically a 4WD vehicle or a boat crossing one of the rivers that run through the park. The most visited lagoas (Azul, Boca da Barra and others) are accessible by the main track from Barreirinhas, but the interior dune field requires guided walking. Tours from Barreirinhas typically run a full day and combine a morning in the dunes with an afternoon at the coastal lagoa at the park's western edge.

The park is one of Brazil's newer and less-visited national parks, and the infrastructure is basic compared to more established parks. There are no large hotel resorts at the park entrance; most visitors stay in Barreirinhas and take day trips into the park. This basic infrastructure is part of what makes the experience feel genuinely remote and undisturbed: the number of visitors is a fraction of those who go to Fernando de Noronha or the Pantanal, and in the early morning the dune field is empty.

Photography at Lencois Maranhenses rewards patience with the light: early morning and late afternoon turn the white sand amber and rose, and the lagoas reflect the sky in mirror-perfect surfaces. Midday light flattens the contrast and the lagoas become less photogenic, but the physical experience of being in the dunes is undiminished. Drone photography that has become popular in the park reveals the patterns of the dune field from above in a way that ground-level walking cannot.

One of the most visually striking and geologically unusual landscapes in South America: a desert of white dunes that fills with vivid blue freshwater lagoons during the rainy season, in a country more associated with rainforest and beaches.

The experience of walking through the dune field and discovering lagoas that were invisible from the crest is a genuinely unique landscape encounter that rewards physical effort over passive observation.

The park is genuinely remote and lightly visited by Brazilian national park standards, making it feel like a discovery rather than a managed tourist experience.