The N4 road is a

national primary road A national primary road ( ga, Bóthar príomha náisiúnta) is a road classification in Ireland. National primary roads form the major routes between the major urban centres. There are 2649 km of national primary roads. This category of ro ...

Ireland Ireland ( ; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the Atlantic Ocean, North Atlantic Ocean, in Northwestern Europe, north-western Europe. It is separated from Great Britain to its east by the North Channel (Grea ...

, running from

Dublin Dublin (; , or ) is the capital and largest city of Republic of Ireland, Ireland. On a bay at the mouth of the River Liffey, it is in the Provinces of Ireland, province of Leinster, bordered on the south by the Dublin Mountains, a part of th ...

to the northwest of Ireland and

Sligo Sligo ( ; ga, Sligeach , meaning 'abounding in shells') is a coastal seaport and the county town of County Sligo, Ireland, within the western province of Connacht. With a population of approximately 20,000 in 2016, it is the List of urban areas ...

town. The M6 to

Galway Galway ( ; ga, Gaillimh, ) is a City status in Ireland, city in the West Region, Ireland, West of Ireland, in the Provinces of Ireland, province of Connacht, which is the county town of County Galway. It lies on the River Corrib between Lo ...

diverges from this route after

Kinnegad Kinnegad or Kinagad () is a town in County Westmeath, Ireland. It is on the border with County Meath, near the junction of the M6 and the M4 motorways - two of Ireland's main east–west roads. It is roughly 60 km from the capital, Dublin ...

, while the N5 to Westport diverges at

Longford town Longford () is the county town of County Longford in Ireland. It has a population of 10,008 according to the 2016 census. It is the biggest town in the county and about one third of the county's population lives there. Longford lies at the meet ...

. Most sections of the N4 that are motorway-standard are designated the M4 motorway.

Road standard

The N4 originates at an intersection with the M50 motorway at Junction 7. This is also Junction 1 of the N/M4. The

Liffey Valley Shopping Centre Liffey Valley Shopping Centre is a shopping centre located in Dublin 22, Ireland which Comprises 80 stores and 20 Restaurants. The centre opened on and is located near the junction of the M50 motorway and N4 road closely surrounded by Lucan ...

is located at Junction 2. The road has three lanes and a bus lane in each direction between the M50 and the start of the M4 at

Leixlip Leixlip ( or ; , IPA: �lʲeːmʲənˠˈwɾˠad̪ˠaːnʲ is a town in north-east County Kildare, Ireland. Its location on the confluence of the River Liffey and the Rye Water has marked it as a frontier town historically: on the border betwee ...

. The N4 was the only one of the main inter-urban national routes whose dual-carriageway section continued into the city centre; however, the section inside the M50 was re-classified as the R148 in 2012. Heading west, the PPP motorway section (see below) ends west of

, and the motorway terminates 5 km further west; it continues as HQDC and bypasses

Mullingar Mullingar ( ; ) is the county town of County Westmeath in Ireland. It is the third most populous town in the Midland Region, with a population of 20,928 in the 2016 census. The Counties of Meath and Westmeath Act 1543 proclaimed Westmeat ...

. From the Mullingar bypass to

Edgeworthstown Edgeworthstown or Mostrim () is a small town in County Longford, Ireland. The town is in the east of the county, near the border with County Westmeath. Nearby towns are Longford 12 km to the west, Mullingar 26 km to the east, Athlone 4 ...

, the road is a wide single carriageway with hard shoulders. Between Edgeworthstown and

Longford Longford () is the county town of County Longford in Ireland. It has a population of 10,008 according to the 2016 census. It is the biggest town in the county and about one third of the county's population lives there. Longford lies at the meet ...

, there is a lower standard single carriageway road. Between Longford and Rooskey single carriageway continues at a higher standard.

Dromod Dromod () is a village in County Leitrim, Ireland. Dromod is a noted fishing village beside Bofin and Boderg, which are threaded by the River Shannon. Built along the River Shannon, this is a Tidy Towns winner with a modern harbour frequented ...

and Rooskey were bypassed in late 2007. This section of the road consists of three roundabouts and a Type 2 dual carriageway, i.e.: two lanes in each direction and no hard shoulder. The road resumes as a single carriageway with hard shoulders until it reaches

Carrick-on-Shannon Carrick-on-Shannon () is the county town of County Leitrim in Republic of Ireland, Ireland. It is the largest town in the county of Leitrim. A smaller part of the town lies in County Roscommon. The population of the town was 4,062 in 2016. It is ...

, where it becomes a local urban road through five roundabouts, and passing over the

River Shannon The River Shannon ( ga, Abhainn na Sionainne, ', '), at in length, is the longest river in the British Isles. It drains the Shannon River Basin, which has an area of , – approximately one fifth of the area of the island of Ireland. The Shan ...

into

County Roscommon "Steadfast Irish heart" , image_map = Island of Ireland location map Roscommon.svg , subdivision_type = Country , subdivision_name = Ireland , subdivision_type1 = Province , subdivision_name1 = Connacht , subdi ...

. The road becomes a high-quality single carriageway bypass 3 km outside of

Boyle Boyle is an English, Irish and Scottish surname of Gaelic, Anglo-Saxon or Norman origin. In the northwest of Ireland it is one of the most common family names. Notable people with the surname include: Disambiguation *Adam Boyle (disambiguation), ...

town, with periodic alternating overtaking lanes passing

Lough Key Forest Park Lough Key Forest Park is an 800-hectare park on the southern shore of Lough Key, 40 km south east of Sligo Town and 3 km east of Boyle, County Roscommon, in the Republic of Ireland. Formerly part of the Rockingham Estate laid out ...

and

Ballinafad Ballinafad () is a village in the south of County Sligo in the west of Ireland. The village overlooks Lough Arrow, and is itself overlooked by the ruins of Ballinafad Castle. Ambrosio O'Higgins, 1st Marquess of Osorno, The 1st Marquess of Osor ...

until it reaches

Castlebaldwin Castlebaldwin or Bellanagarrigeeny () is a townland and small village in County Sligo, Ireland. The castle outside the village of Castlebaldwin is a fortified 17th-century house rather than a medieval castle, with gun slits in the walls and a ...

. From Castlebaldwin to

Collooney Collooney or Coloony () is a town in County Sligo, Ireland. Toponymy Collooney is thought to derive from . Reverend Terrence O'Rorke has previously also suggested ''Culmaine'', as Collooney is designated this way in such works as ''the annals ...

the road is a Type 2 dual carriageway. Funding for the expansion of this section was announced in October 2018, and it opened in 2021. The road becomes near-motorway standard dual carriageway again at Collooney, approaching

Sligo town Sligo ( ; ga, Sligeach , meaning 'abounding in shells') is a coastal seaport and the county town of County Sligo, Ireland, within the western province of Connacht. With a population of approximately 20,000 in 2016, it is the largest urban cen ...

M4 motorway

The section from Leixlip to the west of Kinnegad is the M4

motorway A controlled-access highway is a type of highway that has been designed for high-speed vehicular traffic, with all traffic flow—ingress and egress—regulated. Common English terms are freeway, motorway and expressway. Other similar terms i ...

. The first section of this motorway (Leixlip –

Kilcock Kilcock () is a town and townland in the north of County Kildare, Ireland, on the border with County Meath. Its population of 6,093 makes it the ninth largest town in Kildare and 76th largest in Ireland. The town is located 35 km (22&nbs ...

) was opened on 19 December 1994.

Tolled section of the M4 motorway

Under the Government announcement of the pilot projects on 1 June 1999 this project was to be assessed by the NRA for its suitability to be advanced as a Public-private partnership (PPP). Subsequently, the project was included as one of the projects approved under Tranche II of the PPP Roads programme as announced by the NRA in June 2000. The project involved the construction of 39 km of motorway from Kinnegad to Kilcock and is an extension of the Kilcock-Maynooth-Leixlip motorway on the N4/ N6 Sligo/Galway to Dublin route. The motorway bypasses the towns of Enfield and Kinnegad. The PPP contract was awarded in March 2003 to the EuroLink Consortium (SIAC Construction Ltd and Cintra - Concesiones de Infraestructuras de Transporte S.A.) and allows for them to collect tolls for 30 years from that date. This tolled section (from Kilcock to Kinnegad) opened on 12 December 2005, almost a year ahead of schedule. It is the second-most expensive toll road in Ireland (after the

Dublin Port Tunnel The Dublin Tunnel (Irish: ''Tollán Bhaile Átha Cliath''), originally and still commonly known as the Port Tunnel, is a road traffic tunnel in Dublin, Ireland, that forms part of the M50 motorway. The twin tunnels form a two-lane dual carri ...

). A toll of €3.00 (as of 2022) for cars is charged at a toll plaza just west of Kilcock and at smaller toll plazas at on and off-ramps at Enfield. Between Enfield and Kinnegad, no further access to the M4 is possible. Eurolink operates this tolling scheme, the first in Ireland not operated by

NTR plc NTR plc is an Irish renewable energy company founded in 1978. Today, NTR is an investor in wind energy, focused on Ireland, France, Sweden and the UK. NTR previously held stakes in infrastructure interests including Celtic Anglian Water, Greensta ...

. From 2005 to 2007, Eurolink started to accept several tags issued by other motorways such as M1, M8, eTrip and

tags. On 14 June 2007

joined the Nationwide Electronic Toll Payment System introducing their popular EazyPass tags on the system and allowing all other toll plazas in the country (different from those owned by

) to accept them, meaning that each toll company's electronic tag will work on all toll roads in the State. In the 1 July 2006 edition of the ''

Meath Chronicle The ''Meath Chronicle'' is a local newspaper serving County Meath, Ireland and based in the town of Navan Navan ( ; , meaning "the Cave") is the county town of County Meath, Ireland. In 2016, it had a population of 30,173, making it the ...

'' it was claimed that up to 10% of the €420 million road project had "to be ripped up and replaced" shortly after it opened due to rushed construction, however this cost would have had to be carried by the toll operators, not the state, as per the contract. The bypassed former N4 road has been reclassified as the R148.

Junctions

Motorway reclassification

On 28 August 2009, the

Department of Transport The Department for Transport (DfT) is a department of His Majesty's Government responsible for the English transport network and a limited number of transport matters in Scotland, Wales and Northern Ireland that have not been devolved. The d ...

implemented the second round of proposed reclassifications of dual carriageways as motorways under the ''Roads Act 2007''. A short section of the N4 between Kinnegad (J12) and McNead's Bridge (J13) was affected by this. This extended the M4 westward by 6.8 km.

Bypasses

* Palmerstown – 1984 * Lucan – 1988 * Leixlip, Maynooth, Kilcock – 1994 * Mullingar – 1994 * Longford – 1995 * Drumsna, Jamestown – 1997 * Collooney, Ballisodare – January 1998 * Boyle, Ballinafad – 1998–1999 * Sligo (partial) – September 2005 * Enfield, Kinnegad – December 2005 * Edgeworthstown – June 2006 * Dromod, Roosky – December 2007 * Castlebaldwin – August 2021

Upgrades

In July 2009, an upgrade of the section between the M50 junction and the Leixlip interchange was completed. In this section the road is three lanes in each direction, the median crossings were removed and the junction with the R120 is a fully grade-separated junction. Private accesses and some left turns remain which prevents the section from being designated a

. The speed limit is 80 km/h. There are currently no signal-controlled junctions on the N/M4 between the M50 motorway and the Sligo through-pass. In 2013, a 5 km stretch of dual carriageway with at-grade crossover junctions between the M4 and the Mullingar bypass was upgraded to HQDC. Construction of a 2+2 road at the 15 km stretch between Collooney and Castlebaldwin began in 2019 to improve

road safety Road traffic safety refers to the methods and measures used to prevent road users from being killed or seriously injured. Typical road users include pedestrians, cyclists, motorists, vehicle passengers, horse riders, and passengers of on-roa ...

. The road was opened on 18 October 2021.

Planned improvements to the route

* Mullingar bypass to Longford; 40 km dual carriageway ; at constraints study stage *

; 11 km; at feasibility study stage * Carrick-on-Shannon Bypass; 10 km; preliminary design stage * Cortober to

; 28 km retro upgrade of standard single carriageway road to 2+1 road; at constraints study stage * Sligo Western Relief Road; 8 km; at feasibility study stageN4 Sligo Western Relief Road
* The motorway-style dual carriageway of the N4, running from Collooney—15 km outside Sligo—to Summerhill in Sligo town is not expected to be re-classified as a motorway in the near future.

References

Sources

Roads Act 1993 (Classification of National Roads) Order 2006
–

Roads Act, 1993 (Classification of National Roads) (Kilkock – Kinnegad Route) Order, 2003

Eurolink Motorway M4 website
{{DEFAULTSORT:N4 Road (Ireland) 04 Roads in County Dublin Roads in County Kildare Roads in County Meath Roads in County Westmeath Roads in County Longford Roads in County Leitrim Roads in County Roscommon Roads in County Sligo Road infrastructure in the Republic of Ireland