Chain
A chain is a unit of length traditionally used in land surveying. The most common version is the Gunter’s chain, which equals 66 feet or 22 yards, approximately 20.1168 meters.
The chain was introduced by English clergyman Edmund Gunter in the 17th century to simplify land measurement. One chain consists of 100 links, each 0.66 feet long. It became a standard unit in British and American land surveying and was instrumental in defining land areas, especially in the U.S. Public Land Survey System.
Key Conversions:
1 chain = 66 feet
1 chain = 22 yards
1 chain ≈ 20.1168 meters
10 chains = 1 furlong
80 chains = 1 mile
Though now largely replaced by metric units and modern surveying tools, the chain still appears in older land deeds, maps, and rural property descriptions.
Pole
A pole is another traditional unit of length equivalent to a rod or perch. It measures exactly 16.5 feet, 5.5 yards, or about 5.0292 meters.
The pole has been used historically in land measurement and surveying, especially in England and the United States. Like the rod and perch, it helped standardize measurements of fields, plots, and boundaries before the adoption of metric units.
Key conversions:
1 pole = 16.5 feet
1 pole = 5.5 yards
1 pole ≈ 5.0292 meters
4 poles = 1 chain
40 poles = 1 furlong
Though largely replaced by modern units, the pole remains a notable term in historical surveying and land records.