The 66-foot (20.1 m) chain is divided into 100 links, usually marked off into groups of 10 by brass rings or tags which simplify intermediate measurement.

[5][6] The whole process is repeated for all the other pairs of points required, and it is a simple matter to make a scale diagram of the plot of land.

Surveying with a chain is simple if the land is level and continuous—it is not physically practicable to range across large depressions or significant waterways, for example.

On sloping land, the chain was to be "leveled" by raising one end as needed, so that undulations did not increase the apparent length of the side or the area of the tract.

[8] This unit still exists as a location identifier on British railways, as well as all across America in what is called the public land survey system.

In the Midwest of the US it is not uncommon to encounter deeds with references to chains, poles, or rod units, especially in farming country.

The original of such chains was that constructed, to very high precision, for the measurement of the baselines of the Anglo-French Survey (1784–1790) and the Principal Triangulation of Great Britain.

[15] In France after the French Revolution, and later in countries that had adopted the Metric System, 10-metre (32 ft 9.7 in) chains, of 50 links each 200 millimetres (7.87 in) long were used until the 1950s.