There was once an undersea post office in the Bahamas.
241
The North Atlantic gets 2.5 centimetres (1in) wider every year.
119
If Antarctica's ice sheets melted, the worlds oceans would rise by 60 to 65 metres (200 - 210ft) - everywhere
181
Water is actually naturally blue.
48
There are approximately three million shipwrecks on the ocean floor, worth billions in value and treasure.
22
There are approximately three million shipwrecks on the ocean floor, worth billions in value and treasure.
22
The Caspian Sea is also classed as the world's largest lake.
52