Chesterfield is a market town and a borough of Derbyshire, United Kingdom. It lies north of Derby, on a confluence of the rivers Rother and Hipper. It has a population of 103,800 (2011) , making it the largest town within the administrative borders of Derbyshire, and the second largest settlement in the traditional county after the unitary authority of the city of Derby.
Archaeology of the town traces its beginnings to the 1st century and the construction of a Roman fort, which became redundant and was abandoned once peace was achieved. Later an Anglian village grew up on the site; the name Chesterfield stems from the Anglo-Saxon words 'caester' (a Roman fort) and 'feld' (grazing land).
Chesterfield received its market charter in 1204 and has a moderate sized market on three days a week. The town sits on a large coalfield which formed a major part of the area's economy until the 1980s. Little evidence of the mining industry remains today.
The town's best known landmark is the Church of St Mary and All Saints, popularly known as the 'Crooked Spire' which was originally constructed in the 14th-century.