Liverpool takes the watery part of its name from real Pool. There was a mile-long tidal inlet which flowed in a curve from where the Mersey tunnels now begin down to where the Albert Dock now stands.

'Liver' is thought to stem from the Old English word 'Liefer' which meant 'thick' or 'muddy'.
 

 
The first official reference of Liverpool came in 1192, but it wasn't until 1207 that the then King John officially recognised it's potential as a port and invited invited 200 families to set up a community there.

Soon after this a Castle was built which stood until the civil war when it was destroyed in 1644. By then however Liverpool was becoming an important feature of the new shipping trade, and in 1715 the world's first commercial 'dock' was built, around the old Pool.
 

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