Venice Island was built on a foundation of tree trunks. 1200 years later, those same trunks still support almost all of central Venice.
8
Australia's Great Barrier Reef is 1,250 miles long!
45
More than 25% of the world's forests are in Siberia.
51
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
If Manhattan had the same population density as Alaska, there would only be 15 people living there.
138
The Sahara desert expands at about 1km per month.
90
It takes a drop of ocean water more than 1,000 years to circulate around the world.
61
The longest cave in the world is the 'Mammoth Cave System' in the USA at 560,000 mtrs deep!
63