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 the Blisworth Canal Partnership who's aims are to promote, maintain and improve Blisworth's Canal environment. The village is the site of the Blisworth Tunnel of the Grand Union Canal and one of the longest on the English canal system. The tunnel runs south to the nearby village of Stoke Bruerne. The canal runs to the south-west side of the village and a bridge carries the main road though the village. The bridge is partly original, partly widened, as the main road carried the A43 trunk road until a by-pass was constructed. The A43 (Northampton-Oxford) Milton Malsor and Blisworth by-pass was