The Sahara desert expands at about 1km per month.
90
There are approximately three chickens for every human on Earth.
13
The Amazon rainforest produces more than 20% the world's oxygen supply.
182
Every year, Alaska has about 5,000 earthquakes.
31
Venice Island was built on a foundation of tree trunks. 1200 years later, those same trunks still support almost all of central Venice.
8
An earthquake on Dec. 16, 1811 caused parts of the Mississippi River to flow backwards.
243
The longest cave in the world is the 'Mammoth Cave System' in the USA at 560,000 mtrs deep!
63