The Dundrum bypass, which will be officially opened today, holds the unenviable record of being the most expensive stretch of new road yet built in the State.
With its price-tag of €44.4 million for just 1.2km of roadway, it has cost €37 million per kilometre, mainly because of the acquisition of land at the height of Dublin's property boom.
Construction of the bypass accounted for only €11.4 million of the total bill. The remaining €33 million ended up in the pockets of local land-owners.
Although the scheme has been discussed for more than three decades, arguments over its alignment meant it was not until 1997 that the final version was approved by the minister for the environment, Mr Brendan Howlin.
Further delays followed after it became clear that the acquisition of its linear strip of land would cost three times as much as the estimate.
This required a special contribution of €29.8 million from the Department of the Environment.
As the bypass did not qualify for funding by the National Roads Authority because it was not a "national" road, Dún Laoghaire-Rathdown County Council needed additional State support in order to proceed with the scheme.
The bypass will be officially declared open this afternoon by the Minister for Transport, Mr Brennan, and Cllr Betty Coffey, cathaoirleach of DunLaoghaire-Rathdown County Council, who will unveil a plaque outside Dundrum Library.
The road, which opened in early May, is expected to carry 30,500 vehicles per day, bringing much-needed relief to Dundrum's long-congested main street.