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
Chesterfield Canal Norwood Tunnel. At the time of construction, Norwood Tunnel was the second longest canal tunnel in Britain, exceeded only by another of Brindley's tunnels, that at Harecastle on the Trent and Mersey Canal. The canal was a typical Brindley contour canal, following the contours to avoid costly cuttings and embankments, which resulted in a less than direct route in places. In late 1775, the company had decided to build a branch, which left the canal between Renishaw and Staveley, and ran generally southwards for about to the turnpike road at Norbriggs. This may have been to help with transport to