Richat Structure (Eye of the Sahara)

The Richat Structure, known as the 'Eye of the Sahara,' is one of the most astonishing natural landmarks on the planet. Located near Ouadane on the Adrar plateau, it is an enormous circular formation nearly 40 kilometers across, composed of concentric rings of eroded rock that spiral outward like a target etched into the desert floor. So vast and symmetrical that it was first noticed by astronauts using it as a landmark from orbit, the Eye was long thought to be an impact crater, but geologists now understand it as a deeply eroded geological dome, where ancient layers of rock have been worn down over millions of years to reveal its banded, otherworldly pattern. From the ground, the rings are best appreciated by climbing the surrounding ridges or, for the fortunate, viewing from a light aircraft, where the full scale of the spiral comes into focus. The terrain holds fossils and stone tools hinting at a wetter prehistoric past. Reaching the Eye is an adventure across rugged desert track, usually combined with Ouadane, and rewards travelers with one of Earth's strangest and most humbling landscapes.