[Did you know that?] Did you know that London has a hidden underground river network?

[TheDude @ LCS]

Did you know that London has a hidden underground river network?

Beneath London flow more than 20 buried rivers, including the Fleet, Tyburn, and Westbourne. These rivers were gradually covered over as the city expanded, but they still flow silently under streets, buildings, and even the London Underground, forming a secret watery map beneath the city.

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