Vehicles travelling from the Belfast metropolitan area to the popular resorts around Newcastle must negotiate Ballynahinch town centre with a series of chronically congested junctions. This not only frustrates drivers who are part of the through traffic, but increases tension and danger for those living, shopping and working in the town. The proposed bypass runs round the eastern periphery of the town. Housing is being permitted up to the line of the road, but no further.

The scheme has been proposed since the 1980s, and in the Regional Strategic Transport Plan of 2002 the bypass was earmarked for construction "towards the end" of the plan period, which goes up to 2015. However, this was the plan of the Northern Ireland Assembly, now suspended although land for the road is already protected from development.

In June 2005 the central UK government announced £2m of funding for the scheme and in December 2005 a press release revealed that consultants had been appointed to select a route. This process will also do environmental impact studies and vest land. Thus it is possible that the road could be built by 2010.

Route

The route as currently proposed will start north of the town at the A21 / A24 junction where a Park-and-Share site will also be constructed. It will run generally south east crossing Crossgar Road just east of its junction with Ballylone Road. It will then run south and rejoin the A21 at the current three-way junction of Downpatrick, Crabtree and Drumaness Roads. Junctions (likely roundabouts) will be positioned at the start and end points and also at the point where it crosses Crossgar Road.

The cost of £10.8m publicised in 2005 had increased to £12m by the time this public consultation was released in July 2006.