NYC's Metropolitan Transit Authority (MTA) dumps old subway cars into the ocean to serve as artificial reef.
8
The Caspian Sea is also classed as the world's largest lake.
52
Water is actually naturally blue.
48
The time interval from first sighting of the iceberg that sank the Titanic to impact was a little over 30 seconds.
105
In 1992, 29,000 rubber ducks washed off a ship. They were found thousands of miles away 8 years later.
707
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
The North Atlantic gets 2.5 centimetres (1in) wider every year.
119