Dublin City Council has confirmed that the controversial Dublin Port Tunnel will finally open on December 20th.
The €750m project has been dogged by delays, cost over-runs and leakage problems.
The 4.5km tunnel, which will move traffic from the docklands to the M50 motorway, is opening two years behind schedule.
It will be free to use for trucks, but cars will have to pay a toll.
The council hopes the underpass will remove thousands of heavy vehicles from the city centre every day.