A2 within the Great Britain road numbering scheme in the 1920s. The Dartford Southern By-pass, which relieved chronic congestion on the old route through Dartford, provided considerable local employment during the Post–World War I recession. It was opened by the Prince of Wales in 1924 and is now named Princes Road. It is estimated that the project provided 63,500 days work to local unemployed people. The Dartford Crossing opened as a single tunnel in 1963, then a second tunnel opened in 1980 for additional traffic on the A2, and the M2 Motorway opened in stages between 1963 and 1965 providing an alternative faster route for long-distance traffic avoiding the A2 through Rochester and Chatham. The three-lane stretch of the A2 between Falconwood and Cobham was built in stages from around 1963 until 1973. A section of Ringway 3 (part of the proposed M16 motorway linking to the A2, which later formed part of the M25 motorway opened between 1974 and 1977. The Rochester Way Relief Road, bypassing Kidbrooke and Eltham, was opened in 1988. The M20 motorway to Folkestone was constructed in stages from the 1960s and provided a faster route to Dover following extensions built in the early 1990s, after which traffic levels on the M2 and A2 reduced. The Queen Elizabeth II Bridge opened in 1991. A new flyover for A2 westbound to M25 northbound traffic was completed in late 2007. In 2008, a section of the A2 beside Gravesend was widened to 3 or 4 lanes between Pepperhill (a suburb of Northfleet) to Cobham. It was also rerouted away from the houses of Gravesend/Singlewell to make room for the new lanes and reduce the amount of noise and pollution from the widened roads. The old route of the A2 (the Roman road) has been made into a combined footpath and cycle path. The new road section opened in 2009. A section of the old road has been turned into Cyclopark, with footpaths, cycle paths and an equestrian route along the old road. Proposed developments A new Lower Thames Crossing down river from the Dartford Crossing linking to the A2 has been proposed by the Department for Transport in 2009. The route today Its original alignment roughly followed a mix of the ancient Celtic route and the turnpike road to Dover. The Roman alignment, however, is not easy to identify and much of the original A2 does not