Inside Limerick Bypass (formerly part of N18, downgraded June 2010)
Low standard DC : 2.8 km
Single Carriageway : 4.1 km
The N18 is a very important regional strategic route linking the cities of Limerick and Galway via the large town of Ennis and the major airport at Shannon beside the mouth of the eponymous river.
The old route began in Limerick city centre where it crossed the Shannon.
As Condell Road, it looped up to the Ennis Road.
Turning left, the road reached the townland of Cratloemoyle where Phase 2 of the Limerick Southern Ring Road intersected.
This latter project was opened in July 2010 and bypassed the city section.
(See the M7 page for more detail).
The N18 road then runs for around eight kilometres as a poor-standard dual carriageway, with a lot of hotels and other frontage development.
Next the road passes the popular tourist attraction of Bunratty Castle and a few grade separated junctions.
At the area known as Hurler's Cross, the road was taken on a new alignment in November 2003 that saw it bypass Shannon.
The N19 road, a spur which leads from the N18 through Shannon town to the airport, was also rebuilt nearby as a dual carriageway.
The old N19 passed through the town's main street and is now known as R471.
Shannon town was a planned town designed to act as a population base for the airport and its nearby industrial zones.
North of here, the new route bypasses (September 2002) the old village of Newmarket-on-Fergus before again bypassing (January 2007) the much larger town of Ennis.
The old route wound its way northwest into the town and northeast out of it again, whereas the bypass cuts the corner.
The single carriageway N85 route was also replaced with a new alignment that bypassed the town to the west.
All of these N18 sections were redesignated motorway in August 2009.
Beyond this point, the old route was a winding, narrow country lane, completely unfit for use as a main road connecting two cities.
Another scheme replaced this lane and brought the motorway to Gort in November 2010.
By September 2017, the final segment was in place.
The Gort-Athenry scheme took the route substantially further to the east, intersecting the M6 motorway to the west of Athenry.
From here, the M17 motorway continued the road northwards to Tuam, and a dual carriageway will eventually lead to Sligo.
The only active project on this route is the Newmarket-on-Fergus Motorway Service Area, which is still in planning.