The circular geological feature in Mauritania’s Sahara often called the Eye of the Sahara is the Richat Structure.
The Richat Structure is a prominent, roughly 40-kilometre-wide geological formation near Ouadane in central Mauritania. Its concentric rings are especially visible from space, which made it an important landmark for astronauts and satellite imagery.
Although it resembles an impact crater, geologists interpret it as a deeply eroded dome. Layers of sedimentary and volcanic rock were uplifted and then worn down over a very long period, exposing alternating bands that create the ringed appearance.
The feature was once considered a possible meteorite impact site, but later studies found no convincing evidence of an impact origin. Its nickname can also cause confusion: it is not a city, oasis, or artificial construction, but a natural geological structure in the Sahara.