li
link
Lengthexact by definition
A link is exactly 0.66 feet, 7.92 inches, or 0.201168 metres. It is one hundredth of a surveyor's chain, and it is what made the chain a decimal instrument: distances were booked in chains and links, and areas fell out in acres with no fractions to fight.
| 1 li | 0.201168 m |
Where the unit came from
The links were physical. Gunter's chain was an actual chain of a hundred iron links with brass tags every ten, dragged across the ground by two chainmen. Wear on the links was the dominant survey error for two centuries.
Solvers that use length