League

A historical measure of distance whose value varied, commonly taken at sea as three nautical miles.

The league was traditionally associated with the distance travelled in an hour, but definitions differed between countries, periods and land and sea use. A marine league of three nautical miles is approximately 5.556 kilometres.

It is not a standard unit for modern navigation and should not be used in a calculation without confirming the intended historical definition. The term now appears mainly in older charts, literature and expressions.