Description of km sections Ireland
Last updated 3-12-2017
Only motorways and expressways have km signs. The system was introduced in 2014.
M1 Dublin - Dundalk
Increasing from 0 at the Dublin Ring Road to 90 at the border crossing with Northern Ireland north of Dundalk
M2 Dublin - Monaghan
Increasing from 0 at the Dublin Ring Road to 17 at Ashbourne
M3 Dublin - Kells
Increasing from 0 at the Dublin Ring Road to 66 west of Kells
Signs appear every 500 m.
M4 Dublin - Sligo
Sections:
1 Dublin - Mullingar
Increasing from 0 at the Dublin Ring Road to 73 north of Mullingar
2 Collooney - Sligo
This section does not have kilometerage.
M6 Kinnegad - Galway
Increasing from 0 at Kinnegad to 140.8 at the Galway bypass
Close-up of km 26.5
This sign indicates the distance from this point, not the km values which were introduced some years after this sign was put up.
The first part of the road from Galway is the N6 with green km signs. Integer values appear without decimal.
The Athlone bypass is much older than the rest of the road, and it is still the N6. Normally signs are green along N sections but this one is blue.
Other signs have the right colour.
M7 Dublin - Limerick
Increasing from 0 at the Dublin Ring Road to 187.5 at the junction with the N18 and M20 in Limerick
M8 Portlaoise - Cork
Increasing from 1 at the M7 near Portlaoise to 143.6 at the junction with the N25 and N40 near Cork
M9 Naas - Waterford
Increasing from 0 at the M7 west of Naas to 119 at Waterford
M11 Dublin - Wexford
Increasing from 8.2 at Shankill in Dublin to 100 near Enniscorthy
M17 Galway - Tuam
Increasing from 0 at the Rathmorrissey interchange with the M6 and M18 to 29.5 on the Tuam bypass
M18 Galway - Limerick
Increasing from 9.2 at the Rathmorrissey interchange with the M6 and M17 to 100 at the junction with the M7 and M20 in Limerick
Normally exits are announced 2 km in advance, here 1.8 km
N19 Shannon (N18) - Shannon Airport
Increasing from 0 at the junction with the M18/N18 to 3 at Shannon Business Park
Though the road runs north-south km signs have W and E respectively.
M20 Cork - Limerick
Increasing from 86 at Patrickswell to 95.7 at the junction with the N18 and M20 in Limerick
In future the M20 will in be a north-south route between Cork and Limerick, but it has E(ast)/W(est) km signs. It is unusual that the start point is not the closest to Dublin.
The km values suggest the start point in Cork.
Last exit before Limerick.
N21 Patrickswell - Adare
Increasing from 0 at Patrickswell to 3.0 at Adare
Unlike the M20, the short expressway section of the N21 does have km values starting closer to Dublin.
M50 Dublin ring road
Sections:
1 Harbour Tunnel
This section does not have kilometerage.
2 Western ring road
Increasing from 7 at the junction with the M1 and R139 (former N32) to 45.5 at the M11 near Bray
N85 Ennis southern ring road
Increasing from 0 at the M18 exit to 2.7 at the R458 roundabout
