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
Kessler Tunnel tunnel until 1975 and the rail line was abandoned that same year by the Chessie System, which had taken over the WM and combined the WM's operations with those of the B&O. The National Park Service acquired the tunnel and adjacent portions of the WM right of way in 1980. The site is part of Chesapeake and Ohio Canal National Historical Park. Kessler Tunnel Kessler Tunnel is an abandoned railroad tunnel in Allegany County, Maryland, located about east-northeast of Oldtown. It was built by the Western Maryland Railway (WM) in 1906. It was constructed with concrete arch portals and the