Sagar, city, north-central Madhya Pradesh state, central India. It lies at an elevation of about 2,000 feet (610 metres) and is situated around a lake that is surrounded on three sides by low spurs of the Vindhya Range.
Sagar was founded by Udan Singh in 1660 and was constituted a municipality in 1867. A major road and agricultural-trade centre, it has industries such as oil and flour milling, sawmilling, ghee (clarified butter) processing, hand-loom cotton weaving, bidi (cigarette) manufacture, and railway and engineering works. The city has several Hindu temples, including one dedicated to Chitragupta, the tutelary deity of the Kayasthas (scribes).
Sagar is a centre of higher education. An old Maratha fort located there (completed in 1780) now houses a police training school. The city is the seat of Dr. Harisingh Gour University (1946) and several affiliated colleges. In addition, it has an industrial school, an engineering college, and a school of horsemanship.
Sagar lies on an extensive plain broken by low, forested hills and watered by the Sonar River. Wheat, gram (chickpeas), sorghum (jowar), and oilseeds are the chief crops of the region; there is extensive cattle raising. Sandstone, limestone, and iron ore deposits are worked. The archaeological site at nearby Eran has revealed several Gupta inscriptions. Pop. (2001) city, 232,133; urban agglom., 308,922; (2011) city, 273,296; urban agglom., 370,208.