The Amazon rainforest produces more than 20% the world's oxygen supply.
182
There's a lake under Antarctica that is 25 million years old called Lake Vostok.
109
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
The water between India and Sri Lanka is only 3-30 feet deep and was purportedly passable on foot until 1480 AD when a cyclone moved some sand around.
1
The city of Houston, Texas is built on a swamp and is slowly sinking!
89
It takes a drop of ocean water more than 1,000 years to circulate around the world.
61
Check your map! Virginia extends farther west than West Virginia.
67
An earthquake on Dec. 16, 1811 caused parts of the Mississippi River to flow backwards.
243