Imagine a range of supermountains as tall as the Himalayas, but over three times as long. Seems like you would have heard of these giant mountains, right? Well, they no longer exist.

The Nuna supermountains, which were estimated to be about 5000 miles long (the Himalayas, in comparison, are a mere 1500 miles long), stretched across an entire supercontinent and formed roughly 2 billion years ago. Their disappearance was, in a way, our gain: According to a 2022 study published in Earth and Planetary Science Letters, as the mountains eroded, they sent a deluge of phosphorus, iron, and other nutrients into the ocean, and helped up the amount of oxygen in the atmosphere. This was a boon for evolution. The study suggests that this influx of key nutrients boosted biological cycles that led to the evolution of eukaryotic cells—the very cells that would go on to evolve into lifeforms like animals, plants, and fungi.

The Nuna supermountains aren't the only place we’ve lost. The Pink and White Terraces of New Zealand vanished in 1886. The Sahara desert used to be lush with rivers and fauna. Doggerland, the land that connected Great Britain to mainland Europe, is lost to time.

In the latest episode of The List Show, we're exploring mysterious places from the past that no longer exist. Grab your map and let’s jump in.

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This article was originally published on www.mentalfloss.com as 10 Mysterious Places That No Longer Exist.