What on Earth?

Unsolved Mysteries (2x11)

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In the Namib Desert of west Africa a strange series of rings ranging from 6 to 65 feet wide cover 1200 miles from Angola to South Africa; images taken in 2014 of Mongolia show a strange pattern of rock that may mark the tomb of Genghis Khan; the eye of the Sahara is a 25 mile wide series of concentric circles and remains a mystery; 2008 satellites looking at southern Afghanistan see what maybe an ancient fortress is it connected to the conquest of the area by Alexander the Great; a three mile wide ring is seen in the ice of Lake Baikal, the oldest freshwater lake in the world; in the Gobi Desert of northern China a grid is seen 1-mile long and 0.5-mile wide with a strange line pattern