A furlong is a measure of length that equals 660 feet or 201.168 metres, according to UnitConversion.org. Furlongs are the equivalent of 1/8th of a mile and are used primarily for measuring horse races.
In addition to their use in thoroughbred racing in the United Kingdom, the United States and Ireland, the furlong is also used by railroad repair and maintenance workers in the United Kingdom. Its use within the rail industry dates back to when the tracks and markers were laid, as the older markers are still present. Along with the furlong, race tracks also use miles to measure race distance.