There are different types of Leagues
There are a few different types of League. On this site we have conversions for US Leagues and UK Leagues. In addition, there are also Nautical Leagues which can be found on this site. Please either select the appropriate unit on the selection above of click the required unit in the links below:
What is a League?
A league was originally roughly the distance a person could walk in an hour, about 3 miles (4.8 kilometers). The exact length varied with the country and the period.
A league is an old unit of length, usually around 3 miles or 5 kilometers, though the exact figure varied by country and period. Jules Verne's Twenty Thousand Leagues Under the Sea is about distance travelled, not depth – 20,000 of his 4 kilometer leagues is 80,000 kilometers, twice around the Earth.
What is a micrometer?
A micrometer (µm; micrometre outside the US) is 0.000001 meters. The µ is the Greek letter mu, the SI symbol for the prefix micro.
A micrometer is a millionth of a meter, the scale of things you need a microscope for. A red blood cell is about 7 micrometers across and a human hair about 70.
The unit shares its name with the micrometer screw gauge, the hand tool for measuring small parts. That usually reads to 0.01mm, which is 10 micrometers, so the micrometer mostly doesn't measure in micrometers.