The Dundalk western bypass, part of the M1 motorway between Dublin and the Border, will be officially opened this morning, four months ahead of schedule.
Costing €100 million and measuring 11km (6.8 miles), it will mean a total of 91km of continuous motorway between north Co Dublin and the northern side of Dundalk.
It is the penultimate stage of the upgrading of the Dublin to Belfast road; the final stage will be 14km of high-quality dual carriageway linking the end of the western bypass at Ballymascanlon with the Cloghogue roundabout on the southern side of Newry, Co Down. That road is expected to be completed in 2007.
The western bypass will take about 10,000 vehicles, including heavy goods vehicles, away from Dundalk town centre and reduce peak-time travel by about 30 minutes.
To alleviate gridlock associated with thousands of Gaelic fans who headed to Croke Park for yesterday's matches involving Down and Tyrone, the Taoiseach announced on Saturday the road would open yesterday from 8am until midnight. It was then closed until after Minister for the Environment Martin Cullen officially opens it this morning.
The route of the road meant that a bridge had to be constructed to carry the Dublin-Belfast railway line over the motorway at Ballynahattin. Ian Cunningham, construction manager for Celtic Roads Group (CRG), said the bridge was put into place over 72 hours last Easter, during which the embankment which had supported the track was removed and replaced with the concrete bridge.
Around 25,000 cubic metres of earth were removed and the bridge then slowly pushed into place - it was the first time something like this was done in Ireland, he said.
The western bypass is part of the public-private partnership contract awarded to CRG and includes the Drogheda bypass and the accompanying toll at Gormanston. CRG is responsible for the operation and maintenance of the motorway for the next 28 years.