Mexico City is built on top of an underground resevoir!
47
There are more than 50,000 earthquakes throughout the world every year!
47
The Amazon rainforest produces more than 20% the world's oxygen supply.
182
The Sahara desert expands at about 1km per month.
90
Australia's Great Barrier Reef is 1,250 miles long!
45
If Antarctica's ice sheets melted, the worlds oceans would rise by 60 to 65 metres (200 - 210ft) - everywhere
181
One cubic mile of seawater contains about 50 pounds of gold.
79
The city of Houston, Texas is built on a swamp and is slowly sinking!
89