Preston By-pass Preston By-pass The Preston Bypass was Britain’s first motorway. It was designed and engineered by Lancashire County Council surveyor James Drake as part of a larger initiative to create a north-south motorway network that would later form part of the M6 motorway. The bypass was opened on 5 December 1958 by the Prime Minister, Harold Macmillan. Nearly £3 million was spent in its construction. The original -mile () motorway ran around the east side of Preston between Bamber Bridge (now the M6, Junction 29) and Broughton (now the M55, Junction 1) and crosses over the River Ribble at Samlesbury at
M6 motorway Bay Gateway) has completely re-modelled this junction with a wide additional bridge over the River Lune and other works repositioning slip roads with new acceleration lanes to modern standards. The route was originally intended to replace the old A6, which it does along the northern section starting with the Preston Bypass. However, a much closer approximation to the overall actual route of the M6 (heading north from its southern terminus) is provided by following the A45, A34, A50, A49, then the A6. South of Preston, the A6 route is instead supplemented by the M61 as far as Manchester, with the