
In Ireland, the highest category of road is a motorway (''mótarbhealach'', plural: ''mótarbhealaí''), indicated by the prefix M followed by a one- or two-digit number (the number of the national route of which each motorway forms a part). The motorway network consists entirely of motorway-grade
dual carriageways and is largely focused upon
Dublin
Dublin is the capital and largest city of Republic of Ireland, Ireland. Situated on Dublin Bay at the mouth of the River Liffey, it is in the Provinces of Ireland, province of Leinster, and is bordered on the south by the Dublin Mountains, pa ...
. There are also several three-lane motorways, while Ireland's busiest road, the
M50, incorporates four-lane, five-lane, and six-lane stretches.
The completion of the Major Inter-Urban Motorway Project in December 2010, which saw Dublin connected to the cities of
Cork,
Limerick
Limerick ( ; ) is a city in western Ireland, in County Limerick. It is in the Provinces of Ireland, province of Munster and is in the Mid-West Region, Ireland, Mid-West which comprises part of the Southern Region, Ireland, Southern Region. W ...
,
Waterford
Waterford ( ) is a City status in Ireland, city in County Waterford in the South-East Region, Ireland, south-east of Ireland. It is located within the Provinces of Ireland, province of Munster. The city is situated at the head of Waterford H ...
and
Galway
Galway ( ; , ) is a City status in Ireland, city in (and the county town of) County Galway. It lies on the River Corrib between Lough Corrib and Galway Bay. It is the most populous settlement in the province of Connacht, the List of settleme ...
by continuous motorway, as well as a number of other projects, increased the total length of the country's motorway network to 916 km. Planned new road construction will possibly lead to there being almost 1100 km of motorway by 2035, subject to the availability of funding.
Features
Regulations
Motorways in Ireland have a set of restrictions, which prohibit certain traffic from using the road. The following classes of traffic are not allowed on Irish motorways:
*
Learner drivers
*Slow vehicles (i.e. not capable of reaching 50 km/h (30 mph) on a level road)
*
Invalid carriage
Invalid carriages were usually single seater road vehicles, buggies, or self-propelled vehicles for disabled people. They pre-dated modern electric mobility scooters and, from the 1920s, were generally powered by small gasoline/petrol engines, alt ...
s (lightweight three-wheeled vehicles)
*
Pedestrian
A pedestrian is a person traveling on foot, by wheelchair or with other mobility aids. Streets and roads often have a designated footpath for pedestrian traffic, called the '' sidewalk'' in North American English, the ''pavement'' in British En ...
s
*Pedal-cycles (
bicycles
A bicycle, also called a pedal cycle, bike, push-bike or cycle, is a human-powered or motor-assisted, pedal-driven, single-track vehicle, with two wheels attached to a frame, one behind the other. A is called a cyclist, or bicyclist.
...
, etc.)
*Vehicles under 50cc (e.g.
mopeds
A moped ( ) is a type of small motorcycle, generally having a less stringent licensing requirement than full motorcycles or automobiles. Historically, the term exclusively meant a similar vehicle with both bicycle pedals and a motorcycle engine. ...
)
*Vehicles without
pneumatic tyres
*
Animal
Animals are multicellular, eukaryotic organisms in the Biology, biological Kingdom (biology), kingdom Animalia (). With few exceptions, animals heterotroph, consume organic material, Cellular respiration#Aerobic respiration, breathe oxygen, ...
s
Rules for driving on motorways include the following:
*The keep-left rule applies unless overtaking
*No stopping at any time
*No reversing
*No
hitchhiking
Hitchhiking (also known as thumbing, autostop or hitching) is a means of transportation that is gained by asking individuals, usually strangers, for a ride in their car or other vehicle. The ride is usually, but not always, free.
Signaling ...
*Only vehicles that can travel faster than 90 km/h (55 mph) may use the outside lane
*No driving on the hard-shoulder
The general motorway speed limit is 120 km/h (75 mph).
Specification
Motorways in Ireland are generally constructed to
high-quality dual carriageway
A high-quality dual carriageway (HQDC) is a road category in Republic of Ireland, Ireland. It is defined as an all-purpose dual carriageway road type built to near Controlled-access highway, motorway standards, but without motorway classification ...
standard – with sightlines, curves and elevation designed for 120 km/h speeds. Until recently, all motorways were built with
wide medians in the centre, which typically have a
wire or steel barrier with a continuous hedge growing and covering it over time. The more recent schemes have narrow medians, only 3 metres in width, with a
concrete barrier in the middle. These narrow-median schemes also have reduced carriageway width – a typical narrow-median motorway cross section has two 3.5-metre running lanes, a 2.5-metre hard shoulder and a 1.5-metre central reserve in each direction whereas a typical wide median motorway has 3.75-metre running lanes and a 3-metre hard shoulder. Ireland has only a small amount of D3M (motorway with three lanes in each direction). The
M50 is the most notable example, having been upgraded in parts from a two-lane motorway, to a three or four lane motorway in each direction.
Apart from terminal junctions, motorways can only be accessed using grade-separated junctions. These typically take the form of
roundabout interchanges for higher-capacity junctions, or
dumbbell interchanges – which are a variant on the
diamond-style interchange. – for lower-trafficked interchanges. A number of other types of junction are also used on the motorway network. The M4/M6 and M7/M9 junctions use a variant of the fork style interchange. The M9/N10 junction in County Kilkenny and N40/N28 junction in County Cork are trumpet-style interchange while the M50/N7 and M50/N4 interchanges use partial cloverleaf junctions.
Safety
Motorways in Ireland include several safety features not found on other classes of road. The most notable include the presence of a continuous
hard-shoulder, use of crash barriers, superior lighting and provision of emergency phones at regular intervals. Some motorway schemes include deflectors to provide protection at interchanges.
Signage
Motorway signage in Ireland is blue, and is similar in design to UK signage. Signs for on-line service areas are blue, while those for off-line service areas are brown. Route numbers use the
Motorway typeface, while all other text uses the
Transport Heavy typeface (with Irish text being rendered in a unique
oblique variation).
Signs featuring the motorway number and motorway symbol are positioned at the entrances to motorways, generally on both sides of the slip road. When approaching a junction that leads to a motorway, signs indicating motorway restrictions may be placed in advance.
Route number inheritance
In Ireland all motorways form part of a national route. The M50 was the only motorway that initially did not form part of an existing national primary route, though it was designated as the national primary route N50 in 1994.
In most cases, motorways have been built as a by-pass of a road previously forming the national road (e.g. M7 by-passing roads previously forming the N7). The by-passed roads are then generally reclassified as regional roads. Under Irish legislation (the ''Roads Act 1993''), motorways are sections of roads with special regulations and they are signposted with the M prefix to indicate that they are under motorway regulations.
Present network
The following table shows a list of motorways currently open in Ireland.
History
1983–1989
In 1983, the first sections of Irish motorway were opened: a short section of
M7 bypassing
Naas
Naas ( ; or ) is the county town of County Kildare in Republic of Ireland, Ireland. In 2022, it had a population of 26,180, making it the largest town in County Kildare (ahead of Newbridge, County Kildare, Newbridge) and the List of urban ar ...
and the first stretch of M1 (all of which has now been redesignated M50). The
M1 was later extended in 1985 to
Dublin Airport.
1990–1999
Ireland's motorway network began to expand significantly between 1990 and 1999. The first of the projects completed in this period was the western section of the M50, linking the N7, N4 and N3 together in 1990. This was quickly followed by the M11 Bray/Shankill bypass in 1991. After this there followed a lull in construction after what had been a busy few years in motorway construction by then Irish road building standards. 1993 saw an extension to the M7, continuing from the Naas Bypass and providing a bypass of the town of Newbridge, as well as the M9 Kilcullen spur. In addition, another small section of M1, a bypass of Dunleer in County Louth was opened. The
Leixlip to Kilcock motorway was completed in 1994, forming part of the M4. In 1995 there were no new motorways opened and in 1996 only the northern section of the M50 was opened, linking the existing motorway to the N2 and M1. The Portlaoise bypass opened as M7 in 1997 and like the M1 Dunleer bypass, seemed very isolated compared to the rest of the network which was concentrated around Dublin. 1998 featured the opening of another short piece of M1, this time to the south of Balbriggan, modern day junctions 5 and 7. In 1999 however, there were no new sections of motorway opened.
2000–2010

The first decade of the twenty-first century saw a major expansion in the construction of new motorways in Ireland, after an initially slow start. There were no new motorways opened in 2000 but another section of the M1, extending the Dunleer bypass northwards to the south of
Dundalk
Dundalk ( ; ) is the county town of County Louth, Ireland. The town is situated on the Castletown River, which flows into Dundalk Bay on the north-east coast of Ireland, and is halfway between Dublin and Belfast, close to and south of the bor ...
(junction 16), and the M50 Southern Cross Route were opened in 2001. Continuing the quiet period, 2002 also saw no new motorway in Ireland, but 2003 was a big year. Finally the various sections of M1 were joined, creating continuous motorway from Dublin to just south of Dundalk. A huge part of this route was the
Drogheda
Drogheda ( , ; , meaning "bridge at the ford") is an industrial and port town in County Louth on the east coast of Ireland, north of Dublin. It is located on the Dublin–Belfast corridor on the east coast of Ireland, mostly in County Louth ...
bypass which was tolled. Also in 2003, the M7 was extended westwards from
Newbridge to also bypass Kildare (up to modern day junction 14). A year later in 2004 and this had been extended further with the opening of the
Monasterevin
Monasterevin (), sometimes Monasterevan, is a town in County Kildare, Ireland. It lies on the River Barrow and the Barrowline, a canal branch of the Grand Canal. In the 20 years between the 2002 and 2022 censuses, the population more than dou ...
bypass to link up with the Portlaoise bypass. This meant there was now a continuous motorway from
Naas
Naas ( ; or ) is the county town of County Kildare in Republic of Ireland, Ireland. In 2022, it had a population of 26,180, making it the largest town in County Kildare (ahead of Newbridge, County Kildare, Newbridge) and the List of urban ar ...
to
Portlaoise
Portlaoise ( ), or Port Laoise (), is the county town of County Laois, Republic of Ireland, Ireland.
It is in the Midland Region, Ireland, South Midlands in the province of Leinster.
Portlaoise was the fastest growing of the top 20 largest town ...
.
By 2005, projects were beginning to be completed faster and in this year the M4 was extended from
Kilcock to
Kinnegad, this section of motorway having a toll applied to it, one of the first PPP schemes to be tried out in Ireland. The M1 Dundalk bypass was also finished, meaning that there was now a full motorway link on the Dublin to Belfast route virtually as far as the border. Finally in 2005, the M50 was extended to link up to the M11, providing a full western bypass of the capital. In 2006, the M8
Fermoy
Fermoy () is a town on the Munster Blackwater, River Blackwater in east County Cork, Ireland. As of the 2022 census of Ireland, 2022 census, the town and environs had a population of approximately 6,700 people. It is located in the barony (Ir ...
to
Watergrasshill motorway was opened, another section that was tolled. Also a section of what would become M6 was completed, going westwards from the M4 at Kinnegad to
Tyrrellspass, the road was opened as N6 and was the first section of road to be completed that would be affected by the Roads Act 2007 and motorway redesignation. In 2007 the same road was extended by some 10 km (6 miles) to join with the N52 north of
Tullamore
Tullamore (; ) is the county town of County Offaly in Republic of Ireland, Ireland. It is on the Grand Canal (Ireland), Grand Canal, in the middle of the county, and is the fourth most populous town in the Midland Region, Ireland, Midlands Reg ...
, still opened as N6 as the first tranche of motorway redesignations had only just been submitted.
2008 was one of the most important years for Irish motorways, with a large section of M8 opened, making it the longest motorway in the country. Stretching from
Urlingford to just east of
Mitchelstown, the motorway opened in various sections, the first being the
Cashel
Cashel (an Anglicised form of the Irish language word ''Caiseal'', meaning "stone fort") may refer to:
Places in Ireland
*Cashel, County Tipperary
**The Rock of Cashel, an ancient, hilltop fortress complex for which Cashel is named
** Archbishop ...
bypass, which opened in 2004, and which was followed by the Cashel to Mitchelstown section, both of which were open before the redesignation to motorway came into effect on 24 September 2008. The Urlingford to Cashel section opened later on in the year and so became motorway immediately. Also opened in 2008 was the M9
Carlow
Carlow ( ; ) is the county town of County Carlow, in the south-east of Republic of Ireland, Ireland, from Dublin. At the 2022 census of Ireland, 2022 census, it had a population of 27,351, the List of urban areas in the Republic of Ireland, ...
bypass which was also open to traffic before the redesignation came into effect. Finally, the M6 was extended to the
Athlone
Athlone (; ) is a town on the border of County Roscommon and County Westmeath, Republic of Ireland, Ireland. It is located on the River Shannon near the southern shore of Lough Ree. It is the second most populous town in the Midland Region, Ir ...
bypass and Ireland's motorway network was greatly expanded.
2009 was another major milestone in the development of the Irish motorway network, with many projects under construction finished by the end of the year. Redesignation of High-Quality Dual-Carriageway sections of National Primary routes to motorway took effect on 28 August 2009, further expanding the network. On 18 December 2009 the M6 was opened (Dublin-Galway direct). It is 194 km (120 miles) of motorway. The M9 (linking Dublin to Carlow) was opened on Monday 21 December 2009 and was expanded in March 2010 to link Dublin to Waterford directly. The M9 was fully completed with the opening of the Carlow to Knocktopher section on 9 September 2010.
2010:
M3: 61 km (38 miles) of motorway in County Meath opened on 4 June 2010.
M7: Nenagh – Limerick, 38 km (24 miles) long, opened in three stages, being fully opened on 28 September 2010.
M7: Limerick – Shannon motorway tunnel, 10 km (6 miles) long, opened ahead of schedule on 27 July 2010.
M7: Castletown – Nenagh, 36 km (22 miles) long, opened 22 December 2010.
M7/M8: Portlaoise – Castletown, Portlaoise to Cullahill, 40 km (25 miles), opened on 28 May 2010.
M9: Carlow – Knocktopher, 40 km (25 miles) long, opened 9 September 2010.
M9: Knocktopher – Waterford, 24 km (15 miles) long, opened 22 March 2010.
M50: improvements for Dublin, completed August 2010, but expected earlier.
M18: Crusheen and Gort, 22 km (14 miles), opened 12 November 2010.
Motorway redesignation (tranche 1)
The Roads Act 2007 was passed into law in mid-2007. This Act makes provision for the redesignation of suitable dual carriageways to motorway status. The National Roads Authority made formal applications under Section 8 of the Act to the Minister for Transport on 16 October 2007 regarding dual carriageways which the authority believed to be suitable for redesignation as motorways.
On 29 January 2008, the Department of Transport published notice of the Minister's intention to make the orders being sought and invited submissions or observations to be made to the Minister regarding the NRA's applications.
The consultation procession lasted until 28 March 2008. On 17 July 2008 the
statutory instrument redesignating the roads as motorways was signed, and any open parts of these roads have officially become motorways as of 24 September 2008. The Carlow bypass and Kilbeggan-Athlone roads opened with motorway signage but with temporary 100 km/h (60 mph) general speed limits between their opening and their official re-designation as motorways.
The following sections were redesignated:
Motorway redesignation (tranche 2)

On 30 September 2008, the NRA announced its second tranche of proposed motorway redesignations. The closing date for submissions was 14 November 2008 and the
Statutory Instrument reclassifying the roads as motorways was made on 2 July 2009, taking effect from 28 August 2009.
The following schemes were included:
On the N6, the Athlone bypass had also been included in the proposed redesignations. However, the final order (''the Roads Act 2007 (Declaration of Motorways) Order 2009'') did not include this section. However, the section of the N9 road between Powerstown and Waterford, which had been proposed as part of the first tranche but not included in the final order, was included in this order.
Inter-urban motorways
Linking Dublin to regional cities. These motorways are:
*
M1 – linking Dublin with Dundalk (and dual carriageway to link in with Northern Irish motorway network)
*
M6 (via
M4) – linking Dublin with Galway (Officially opened, 18 December 2009 and the first city to city motorway in Ireland)
*
M7 – linking Dublin with Limerick
*
M8 – linking Dublin with Cork
*
M9 – linking Dublin with Waterford (completed 9 September 2010)
All sections of these motorways were completed by the end of 2010. The completion of these schemes added more than 300 km (200 miles) of motorway to the network at the time.
2015–present
Atlantic Corridor
Under the government's
Transport 21 initiative,
Letterkenny
Letterkenny ( , meaning "hillside of the O'Cannons"), nicknamed the Cathedral Town, is a large town in County Donegal, Ireland, on the River Swilly in the north-west of Ulster. Along with the nearby city of Derry, Letterkenny is a regional eco ...
will be linked to Waterford and Cork with new high quality roads – collectively known as the "
Atlantic Corridor
The Atlantic corridor or Atlantic motorway is a proposed road project in Ireland. The scheme, announced in 2005, was intended to link Waterford in the South-East to Letterkenny in the North-West via motorway or dual carriageway by 2015. Howev ...
". While it is anticipated much of this scheme will be constructed as either 2+2 dual carriageway or higher quality single-carriageway – a significant portion of it is expected to be constructed as motorway.
* The
M20 scheme linking Cork with Limerick (the state's second and third largest urban areas), will provide a complete connection between the two cities. It will be approximately 90 km (56 miles) in length. Its construction was given the final go-ahead on 13 October 2017.
* The final
M18 scheme connecting Gort to the M6 near Galway city opened ahead of schedule on 27 September 2017.
* The construction of the
M17 was bundled with the final M18 component and also opened on 27 September 2017. The two motorways meet at Rathmorrissey Interchange, Co. Galway.
Other motorways
On 18 July 2019, the
M11 Enniscorthy
Enniscorthy () is the second-largest town in County Wexford, Republic of Ireland, Ireland. The town is located on the picturesque River Slaney and in close proximity to the Blackstairs Mountains and Ireland's longest beach, Curracloe.
The Plac ...
bypass was opened. A scheme to widen the
M7 from two to three lanes in each direction from the beginning of the Naas bypass, at junction 9, to the M7/M9 merge near Newbridge, junction 11, was completed in November 2019.
A motorway project, the
Dublin Outer Orbital Route, may be progressed in the future. It is possible that a motorway will be built to the north of
Cork City
Cork ( ; from , meaning 'marsh') is the second-largest city in Republic of Ireland, Ireland, the county town of County Cork, the largest city in the Provinces of Ireland, province of Munster and the List of settlements on the island of Ireland ...
to link the existing
N22,
N20 and
M8 routes: this route, if built, will most likely be designated as the N40. Other potential motorways include a possible extension of the
M4 from
Mullingar
Mullingar ( ; ) is the county town of County Westmeath in Ireland. It is the third most populous town in the Midland Region, Ireland, Midland Region, with a population of 22,667 in the 2022 census of Ireland, 2022 census.
The Counties of M ...
to
Longford
Longford () is the county town of County Longford in Ireland. It had a population of 10,952 at the 2022 census. It is the biggest town in the county and about one third of the county's population lives there. Longford lies at the meeting of ...
and the
Galway City
Galway ( ; , ) is a City status in Ireland, city in (and the county town of) County Galway. It lies on the River Corrib between Lough Corrib and Galway Bay. It is the most populous settlement in the province of Connacht, the List of settleme ...
Outer Bypass which may be built as an extension to the M6.
The Cork to Ringaskiddy road improvement scheme, originally envisaged as dual-carriageway, will now proceed as a motorway scheme.
The planned Adare – Rathkeale dual carriageway, being progressed as part of the Limerick to
Foynes improvement scheme, may proceed as a motorway scheme.
Motorway service areas
This is a list of motorway
service stations operating in
Ireland
Ireland (, ; ; Ulster Scots dialect, Ulster-Scots: ) is an island in the North Atlantic Ocean, in Northwestern Europe. Geopolitically, the island is divided between the Republic of Ireland (officially Names of the Irish state, named Irelan ...
.
TII is building a series of
service areas across the motorway network to provide for safe rest areas. The first of these opened on 15 September 2010 on the
M1 at Lusk.
Tranche 4 Motorway Services were announced in 2016 and are proposed for the following locations:
*M3 – Dunshaughlin
*M6 – Oranmore (also accessible from M17/M18)
*M18 – Newmarket-on-Fergus
The following sites have also been proposed:
*M20 – Charleville
*M28 – TBD
*N69 – TBD
Originally, service areas were to be located at 12 locations, but a recent
An Bord Pleanála decision ruled that a service area to be located at Rathmorrissey at an M6 junction be removed from an adjacent scheme.
It is anticipated that service areas will be provided on both the M3 motorway and the proposed M20 and M28 motorways.
See also
*
Roads in Ireland
The island of Ireland, comprising Northern Ireland and the Republic of Ireland, has an extensive network of tens of thousands of kilometres of public roads, usually surfaced. These roads have been developed and modernised over centuries, from ...
*
List of motorways in Northern Ireland
*
History of roads in Ireland
*
National Roads Authority
*
Evolution of motorway construction in European nations
*
Latoon fairy bush, a tree that purportedly necessitated the shifting of the M18 to avoid its destruction
References
{{DEFAULTSORT:Motorways in the Republic of Ireland
Motorways in
Republic of Ireland transport-related lists
de:Straßensystem in Irland
ga:Bóithre agus mótarbhealaí in Éirinn
gv:Raaidyn ayns Pobblaght Nerin
it:Strade irlandesi