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
Northamptonshire the M1 motorway, the A43 between Northampton and the county boundary near Stamford, the A361 between Kilsby and Banbury (Oxon) and all B, C and Unclassified Roads. Since 2009 these highways have been managed on behalf of the county council by MGWSP, a joint venture between May Gurney and WSP. Two major canals – the Oxford and the Grand Union – join in the county at Braunston. Notable features include a flight of 17 locks on the Grand Union at Rothersthorpe, the canal museum at Stoke Bruerne, and a tunnel at Blisworth which, at , is the third-longest navigable canal