Did you know?
Length of the USA / Canada border (8,890 km) is about as big as Length of the Great Wall of China (8,850 km)
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Forest in Cameroon (2011) (198,300 km^2)
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.