I love this kind of stuff:
SPACE.com -- Huge Crater Found in Egypt:Hard to believe they only found it now.
Scientists have discovered a huge crater in the Saharan desert, the largest one ever found there.
The crater is about 19 miles (31 kilometers) wide, more than twice as big as the next largest Saharan crater known. It utterly dwarfs Meteor Crater in Arizona, which is about three-fourths of a mile (1.2 kilometers) in diameter.
In fact, the newfound crater, in Egypt, was likely carved by a space rock that was itself roughly 0.75 miles wide in an event that would have been quite a shock, destroying everything for hundreds of miles. For comparison, the Chicxulub crater left by a dinosaur-killing asteroid 65 million years ago is estimated to be 100 to 150 miles (160 to 240 kilometers) wide.
The crater was discovered in satellite images by Boston University researchers Farouk El-Baz and Eman Ghoneim.