The N2 was a straight road winging its way out of Dublin in a north-northwesterly direction, striking out for Derry. Beyond about Slane, is reverts to a winding country road. Near Dublin, it passes the large satellite town of Ashbourne.
In May 2006, a 17km high quality dual carriageway replacement for this latter section opened. In August 2009, 13km of this was reclassified M2, creating a new motorway.
The rest of the road is single carriageway. There is a long-term plan to upgrade from Ardee to the border to dual carriageway or motorway in order to tie in with another proposed dual carriageway, the A5, in Northern Ireland, which together would create a new route between Dublin and Derry.
Update 05/06/2020:
It has been announced that the Slane Bypass will be built as single carriageway, and not dual as previously indicated.
The scheme now moves to design phase.
The preliminary cost is €38 million and will include traffic management measures within Slane.
The preferred route map is here.
Update 12/07/2019:
The Slane Bypass is at Route Selection with announcement of the preferred route overdue now.
Ashbourne-Kilmoon Cross, Clontibret-NI Border and Ardee-Castleblayney are still all at feasibility study.
Update 28/11/2020:
Ashbourne-Kilmoon Cross, Ardee-Castleblayney and Clontibret-NI Border dual carriageways are at route selection.
Update 25/02/2021:
The preferred routes for the two new N2 schemes have been published.
The one for the N2 - Clontibret-NI Border scheme is here and Ardee to Castleblayney is over here.
The northern scheme "cuts the corner" as it passes Monaghan and will shorten the distance a good bit (about 1.5 km) as well as allowing it to be taken at higher speed.
The southern scheme, on the other hand, follows the existing road very closely and will probably be built alongside it in the manner of the N4 Collooney-Castlebaldwin scheme which is currently under construction.
Update 07/03/2021:
There is another round of public consultation underway on the N2 Ashbourne-Kilmoon Cross scheme. An emerging preferred route has been picked. Planners went with E-2: this route runs immediately to the west of the N2 until the R155, then swings further west before coming back to hit Kilmoon Cross.
The Round 3 Consultation is available on the official scheme site. The emerging route can be found in it. The interfaces at either end haven't been nailed down yet and are still shown as large hatched areas.
For reference, here is the map showing all options from last summer.
Update 07/06/2021:
The Slane bypass is making progress.
It has been signalled that it is due for submission to An Bord Pleanala (Planning Board) by Q2 2022 - around a year away.
It aims to provide a short single carriageway bypass of this town which has an unusual layout and suffers greatly from traffic congestion, especially from trucks and lorries.
Update 04/10/2021:
For the Slane bypass here is the update from the TII: "A preferred route has been identified.
The detailed design and preparation of the statutory documents are underway.
Phase 3 - Design and Environmental Evaluation, expected to be complete in Q3 2021.
The preliminary business case is being progressed.
It is anticipated that this scheme will proceed to planning approval late 2021 or early 2022.
This scheme will be progressed with a public realm scheme."
Update 24/02/2022:
The Option Selection Report for the N2 Ashbourne-Kilmoon Cross scheme has been published. Here are some extracts.
On page 7-74 (PDF page 200), section "7.5.4.2 Analysis":
"A Type 1 Dual Carriageway cross-section has been proposed for all route options".
Separately it is confirmed that motorway would be "excessive" so the Type 1 road will not open as one.
According to the section "7.1.1.4 Preliminary Junction Strategy", there will be no intermediate junctions, the northern tie-in will be a roundabout, and the southern tie-in a grade separated junction.
Previously it was hoped that the Tayto Park amusement park would get its own junction as it is a large traffic generator especially in summer and is currently expanding.
This is a preliminary strategy however and so is subject to revision.
From the section "7.1.1.8 Route Option E-2" (the chosen option), here is a description of the proposed route:
"This option consists of a section of online widening of the existing N2 from the tie in with the M2
motorway at the southern junction corridor at Rath ... This option then diverges from the existing N2 and bypasses the
Primatestown junction in an offline section to the west of the existing N2. The offline section crosses
the R155 ... The offline section then ties in with the existing N2 and the R152 at the northern junction corridor at Kilmoon."
It isn't clear if the "online widening" of the existing N2 will result in the removal of a parallel single-carriageway road in order to cater for local traffic or if a new road will be provided for this purpose.
The latter option is the more likely as it is best practice.
Update 06/11/2022:
The preferred route for N2 Ardee-Castleblayney has been made available on a GIS site.
The scheme incorporates the 2005 Carrickmacross bypass, which will be dualled, and 6 new grade-separated junctions will be provided.
Two existing junctions at Carrickmacross will be modified and expanded.
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