More than a dozen men have stood on the surface of the moon, but only three have been to Challenger Deep in the Marianas Trench, the deepest known spot in the ocean.
17
Mexico City is built on top of an underground resevoir!
47
The water of the Antarctica is so cold that nothing can rot there.
334
An earthquake on Dec. 16, 1811 caused parts of the Mississippi River to flow backwards.
243
There are more than 50,000 earthquakes throughout the world every year!
47
The Niagara Falls moves upstream at an average rate of about 295ft a century!
48
The Atlantic Ocean is saltier than the Pacific Ocean.
54