Lençóis Maranhenses looks like a desert, but it's alive with shimmering pools, remote villages and ancient paths that only local guides know how to read.

I was at least 20 steps behind my group – and another 30 behind our guide – when he suddenly stopped, checked his watch and tilted his face toward the sky, as if taking cues from the Sun.

"We must be lost," I thought. Smooth, pale slopes rose and fell in every direction, with glistening teal pools woven between them. It was a landscape with no obvious beginning or end. Then, as if reassured, our guide carried on, following a trail only he could see.

My three friends and I were a few hours into a three-day trek across Lençóis Maranhenses National Park, a humbling expanse of sand in north-eastern Brazil, and I had already lost all sense of direction. I walked in silence, listening to the wind, the rippling water, the sand crunching beneath my feet.

With each step, I sank a few centimetres, forcing my foot to work twice as hard. I kept falling behind, switching from flip-flops to water shoes and finally bare feet as the sand shifted from soft powder to a rock-hard surface baking in the heat. A friend back home had done a similar trek; "You'll feel bones you never knew existed in your feet," they'd warned. I was starting to believe them.    

Bordered by lush vegetation on one side and the Atlantic Ocean on the other, Lençóis Maranhenses is one of Brazil's most unusual ecosystems. Strong coastal winds push sand inland, creating a desert-like landscape that spans 1,500 sq km (579 sq miles), with dunes rising up to 30m (98ft).

But Lençóis is no desert. During the wet season (January to June), so much rain falls that water settles in natural basins between the dunes. A compact layer of impermeable sediment keeps the rainwater from draining, forming the hundreds of freshwater lagoons that travellers like me come to swim, wade and float in.

Our first day on the dunes began just after sunrise. Our guide, Carlos Otávio Rêgo – known to everyone as Tav – set a steady pace from the start. We quickly reached our first descent, and I awkwardly slid down the sand using my feet as makeshift skis, trying my best not to be the first one to fall. 

From below, the dunes took on a different scale – towering ridges and shadowed curves that looked impossible to climb. We passed lagoons so big they stretched on like rivers – and crossed several of them, sometimes holding our packs over our heads in waist-deep water.

A little more than an hour in, it was time for our first dip.

"How's this one?" Tav asked, pointing at a perfect bowl-shaped lagoon, its water so clear it looked polished. I barrelled forward, unable to control my momentum, and crashed in with a loud splash.

It's these ephemeral pools that make Lençois like nowhere else on Earth. It's also what helped earn the park Unesco World Heritage status in 2024. With that recognition came a new global spotlight, said Cristiane Figueiredo, head of the national park. The most recent numbers prove her point: in 2024, Lençóis received a record 552,000 visitors. By September this year, that number had already surpassed 580,000.

The park is now one of Brazil's most sought-after destinations among international travellers, ranking fourth in 2024 behind only Sugarloaf Mountain, Christ the........

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