The Sahara desert expands at about 1km per month.
90
The longest cave in the world is the 'Mammoth Cave System' in the USA at 560,000 mtrs deep!
63
Europe is the only continent without a desert.
62
More than 25% of the world's forests are in Siberia.
51
The state with the longest coastline in the Continental U.S. is Michigan.
31
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