In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described Harrowby like this:
HARROWBY, a township in Grantham parish, Lincoln; adjacent to the Grantham and Nottingham canal, 1 mile W of Grantham. Real property, £3, 072. Pop., 118. Houses, 19. The manor belonged to the Rolts; passed, about the middle of last century, to the Ryders; and gives them the title of Earl. Harrowby Hall was formerly the seat of the earls, but is now otherwise occupied.
GB Historical GIS / University of Portsmouth, History of Harrowby, in South Kesteven and Lincolnshire | Map and description, A Vision of Britain through Time.
Date accessed: 27th March 2017
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