10 of the tributaries flowing into the Amazon river are as big as the Mississippi river.
41
It takes a drop of ocean water more than 1,000 years to circulate around the world.
61
The warmest temperature ever recorded on Antarctica was 3 degrees F.
175
An earthquake on Dec. 16, 1811 caused parts of the Mississippi River to flow backwards.
243
The Niagara Falls moves upstream at an average rate of about 295ft a century!
48
Europe is the only continent without a desert.
62
There's a lake under Antarctica that is 25 million years old called Lake Vostok.
109