Earth Paints – Eye of the Sahara, Africa (photo)

The Eye of the Sahara is one of the geological marvels of our world. This phenomenal sight is located in the Sahara Desert in western Mauritania. It is approximately 30 miles (48 km) in diameter. It is actually visible from orbit. It is believed to be the result of the effects uplift and erosion, although geologists admit that they are not certain about that, and are entirely mystified as to the cause of its circular shape.