How do I convert feet to chains?
Divide by 66. A Gunter's chain is exactly 66 feet (22 yards, or 20.1168 m), so 330 feet is 5 chains.
500 feet is about 7.58 chains, or 7 chains and 58 links if you do it the surveyor's way – a link is a hundredth of a chain, 7.92 inches.
Edmund Gunter, who designed the chain for surveying in 1620, is also credited with coining the words cosine and cotangent.
What is a foot?
The foot is an imperial and US unit of length equal to 12 inches, or exactly 30.48 centimeters. It is a third of a yard and 1/5,280 of a mile.
The foot began as the length of a human foot, and so differed from place to place and from person to person. The modern international foot was fixed at exactly 0.3048 meters by agreement in 1959.
People's height is given in feet and inches in the US and UK, and aircraft altitude is given in feet nearly everywhere, metric countries included.
What is a chain?
The chain is a surveying unit of 66 feet, which is exactly 20.1168 meters. It is divided into 100 links of 7.92 inches each, and 80 chains make a mile.
The chain was devised by the English mathematician Edmund Gunter around 1620 and used to survey land. Ten square chains make exactly an acre, which is why surveyors liked it. GPS has replaced it for most work, though US public land surveys are still recorded in chains and links.