Grantham is a market town in the South Kesteven district of Lincolnshire, England, situated on the banks of the River Witham and bounded to the west by the A1 road. It lies some 23 mi south of Lincoln and 22 mi east of Nottingham. The population in 2016 was put at 44,580. The town is the largest settlement and the administrative centre of South Kesteven District.