League (unit)
A league is a unit of length (or, in various regions, area). It was common in Europe and Latin America, but is no longer an official unit in any nation. The word originally meant the distance a person could walk in an hour. Since the Middle Ages, many values have been specified in several countries.
On land, the league was most commonly defined as three miles, though the length of a mile could vary from place to place and depending on the era. At sea, a league was three nautical miles (3.452 miles; 5.556 kilometres). English usage also included many of the other leagues mentioned below (for example, in discussing the Treaty of Tordesillas).
The league was used in Ancient Rome, defined as 1 1⁄2 Roman miles (7,500 Roman feet, modern 2.2 km or 1.4 miles). The origin is the leuga Gallica (also: leuca Gallica), the league of Gaul.
The Argentine league (legua) is 5.572 km (3.462 mi) or 6,666 varas: 1 vara is 0.83 m (33 in).
In Portugal, Brazil and other parts of the Portuguese Empire, there were several units called league (Portuguese: ):
The names of the several léguas referred to the number of units that made the length corresponding to an angle degree of a meridian arc.
As a transitory measure, after Portugal adopted the metric system, the metric légua, of 5.0 km, was used.
In Brazil, légua is still used occasionally in the country, where it has been described as about 6.6 km.
The French lieue – at different times – existed in several variants: 10,000, 12,000, 13,200 and 14,400 French feet, about 3.25 km to about 4.68 km. It was used along with the metric system for a while but is now long discontinued.
As used in Jules Verne's Twenty Thousand Leagues Under the Sea, a league is four kilometres.
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