ultrafacts:The Richat Structure, also known as the Eye of the Sahara and Guelb er Richat, is a promi


ultrafacts:The Richat Structure, also known as the Eye of the Sahara and Guelb er Richat, is a promi
ultrafacts:The Richat Structure, also known as the Eye of the Sahara and Guelb er Richat, is a promi