Did you know?
Height of Niagara Falls (57 m) is about as big as Height of the Leaning Tower of Pisa (56.7 m)
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Duration of Frankish Empire (700 y)
If this was a standard unit ...
Yes, there's now a book based on these numbers. Oxford University Press: July 2018.
Click here to learn more about it.
Click here for Podcast: Andrew Elliott interviewed for New Books Network.