It Looks Like a Desert. But It Has Thousands of Lakes

Lençóis Maranhenses sits at the intersection of three biomes—a rare overlap that supercharges biodiversity. Across 350 square miles of dunes, the rainy season brings thousands of crystal blue lagoons into view, many big enough to swim in. What makes this surreal environment possible? And why, even after 2 million years in existence, does it still feel so mysterious?

Untold Earth explores the seeming impossibilities behind our planet’s strangest, most unique natural wonders. From fragile, untouched ecosystems to familiar but unexplained occurrences in our own backyard, this series chases insight into natural phenomena through the voices that know them best.

Untold Earth is produced in partnership with Atlas Obscura and Nature.

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Correction (October 30, 2025): This video's co-producer's name is correctly spelled Beatriz Maglione. The on-screen credit contains a misspelling. Our sincere apologies for the error — and thank you for your fantastic work, Beatriz!