district, administrative and historic county of Derbyshire, England. The district surrounds Chesterfield on three sides. The east and north are part of a major coalfield, though less important than formerly. Iron, steel, and heavy engineering industries are significant at Clay Cross, Dronfield, Eckington, Renishaw, and other towns on the eastern side of the district. Dronfield and Eckington are also residential areas for commuters to neighbouring Sheffield. In the west and south the district is more rural in character. The land rises in the west toward the Pennines, and part of the district is within the Peak District National Park. The district's council meets in neighbouring Chesterfield. Area 107 square miles (276 square km). Pop. (2001) 96,935.