Grand Junction Canal Nene at Northampton, to the turnpike road at Old Stratford (north-west of the modern Milton Keynes), and to Watford in Hertfordshire: those to Daventry and Watford were not built. The branch to Old Stratford was amended before it was built (see below). The branch to Northampton was delayed as the plans of the Leicestershire and Northamptonshire Union Canal to reach Northampton and thus join with the Grand Junction came to nothing. The link to Northampton was made by a tramroad transferred from Blisworth Tunnel, with the 5-mile (8-kilometre) canal from Gayton being opened in 1815. The link to Leicester was
Indigo Tunnel of the parallel Baltimore and Ohio railroad line on the opposite side of the Potomac River. The tunnel was acquired by the National Park Service in 1980 and became part of Chesapeake and Ohio Canal National Historical Park. The Park Service has identified bat colonies living in the tunnel and has closed the tunnel to the public in order to protect the colonies. Indigo Tunnel Indigo Tunnel is an abandoned railroad tunnel in Allegany County, Maryland, located about east of Little Orleans. Built by the Western Maryland Railway (WM) in 1904, Indigo was the company's longest tunnel. It was part