These sand dunes in Iran look like they're straight out of a cartoon — but they're real and insanely dangerous

In the heart of Dasht-e Kavir, a large desert in Iran, there is an enormous area of sand dunes known as Rig-e Jenn. At about 1,400 square miles, it is said to be one of the most impossible areas in the world to pass through. 

There are no routes, no trails, no water — just the crazy hills of insanely soft sand. Knowledge of the dunes has come from only the handful of researchers that have dared to explore it, but even caravan travelers in the area avoid this area.

A brave, Danish traveler and photographer, Thomas Flensted, paired up with RO Nature, a team of Iranian safari travel experts, and took on the dangerous challenge of traveling through Rig-e Jenn. Here's what their four days of travel were like. 

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Flensted and his team spent four days and three nights in the deserts of Iran.

They met up in Tehran, Iran, and drove almost a full day to get to the dunes. Since the dunes are in the middle of the desert, it was very tough to get there.

The group drove for many hours on the highway, making their way to the back roads, over a dry river, then straight through the desert before they could see the dunes. By the time the group got there the first day, it was already time to set up camp for the night.