Blisworth Limestone Formation today in the seas off the Bahamas (Kirkaldy p. 59). Much of it also contains marine shells, notably of oyster. Subsequently, the site was submerged less deeply so that the overlying Blisworth Clay was deposited in brackish conditions. (Gallois p. 20) The stratum is known as Blisworth Limestone because it was first studied at Blisworth in Northamptonshire when the Blisworth tunnel was being dug for what is now called the Grand Union Canal. The tunnel finally opened in 1805. Blisworth limestone is a generally thin but widely spread deposit in eastern England. It becomes thicker as one progresses southward from
Blisworth railway line remains, electrified in the 1960s and is now part of the West Coast Main Line running 125 mph trains from London Euston to Glasgow. The Northampton Loop of the line leaves the main line at Roade, north of Roade cutting and just south of Blisworth, taking trains on into Northampton and further north to re-join the main line at Rugby. The Stratford-upon-Avon and Midland Junction Railway ran from Blisworth station south to , Banbury and but closed in the 1960s. Much of the infrastructure such as cuttings and bridges remain along the route. During the nineteenth and twentieth