Blisworth Limestone Formation relationship to the Jurassic ridge, to the west of Peterborough. (BGS sheet 157) Around Towcester it reaches a thickness of 9m. (Hains & Horton p. 85) Blisworth limestone is used as a building material, in particular as blocks of stone. Lilford Hall in Northamptonshire is made from Blisworth limestone. Blisworth Limestone Formation The Blisworth Limestone Formation is a geological formation primarily consisting of limestone deposited during the Bathonian stage of the Middle Jurassic, found in the Jurassic ridge which extends north and south through England. It was laid down in the shallows of the Jurassic sea and is part of
Sapperton Canal Tunnel workmanship, as it had to be closed for ten weeks after only a year, while repairs were carried out. It was superseded as the longest canal tunnel in England in 1811 by the Huddersfield Narrow Canal's Standedge Tunnel, which was long when built, later extended to to accommodate the adjacent railway tunnel, and remains the highest, longest and deepest canal tunnel in Britain - though, unlike Sapperton, Standedge can only accommodate . Strood Tunnel on the Thames and Medway Canal was also longer at when it opened in 1824, but was cut in two in 1830 by opening out a