The Caspian Sea is also classed as the world's largest lake.
52
The North Atlantic gets 2.5 centimetres (1in) wider every year.
119
NYC's Metropolitan Transit Authority (MTA) dumps old subway cars into the ocean to serve as artificial reef.
8
Water is actually naturally blue.
48
There was once an undersea post office in the Bahamas.
241
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 roar that we hear when we place a seashell next to our ear is not the ocean, but rather the sound of blood surging through the veins in the ear.
476