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The Greek, Olympian foot, (taken presumably from the stadium length, divided by 600) is cited as 1.01376 English feet. 6000 of these Olympian feet equals 6082.596 feet. The UK officially defined nautical mile is cited as 6082.56 feet. (Figures taken from Neal’s book)

This from Wikipedia...

A nautical mile is a unit of length used in air, marine, and space navigation, and for the definition of territorial waters.[2][3] Historically, it was defined as the meridian arc length corresponding to one minute (1/60 of a degree) of latitude. Today the international nautical mile is defined as exactly 1,852 metres (6,076 ft; 1.151 mi).

https://en.wikipedia.org/wiki/Nautical_mile