The Niagara Falls moves upstream at an average rate of about 295ft a century!
48
A volcano has enough power to shoot ash as high as 50 km into the atmosphere.
59
The longest cave in the world is the 'Mammoth Cave System' in the USA at 560,000 mtrs deep!
63
Every person in the world can fit in Texas and be given over 1000 sq ft in which to live.
14
The Dallas/Ft. Worth airport is larger than New York City's Manhattan Island.
62
The Sahara desert expands at about 1km per month.
90
The city of Houston, Texas is built on a swamp and is slowly sinking!
89