County Carlow ( KAR-loh; Irish: Contae Cheatharlach) is a county located in the Southern Region of Ireland, within the province of Leinster. Carlow is the second smallest and the third least populous of Ireland's 32 traditional counties. Carlow County Council is the governing local authority.
The county is named after the town of Carlow, which lies on the River Barrow and is both the county town and largest settlement, with over 40% of the county's population. Much of the remainder of the population also reside within the Barrow valley, in towns such as Leighlinbridge, Bagenalstown, Tinnahinch, Borris and St Mullins. Carlow shares a border with Kildare and Laois to the north, Kilkenny to the west, Wicklow to the east and Wexford to the southeast.
Carlow is known as "The Dolmen County", a nickname based on the Brownshill Dolmen, a 6,000-year-old megalithic portal tomb which is reputed to have the heaviest capstone in Europe, weighing over 100 metric tonnes. The town of Carlow was founded by the Normans in 1207 and the county was shired shortly thereafter, making it one of the oldest counties in Ireland. During the 14th century, the county was the seat of power of the Kingdom of Leinster, as well as the capital of the Lordship of Ireland from 1361 to 1374.

Etymology
The county was named after the town of Carlow, which is an anglicisation of the Irish Ceatharlach. Historically, it was anglicised as Caherlagh, Caterlagh and Catherlagh, which are closer to the Irish spelling. In the 19th century, John O'Donovan, a scholar working with Ordnance Survey Ireland, hypothesised that the origin of the name was Ceatharloch (meaning "quadruple lake"), since ceathar means "four" and loch means "lake". It is therefore directly translated as "Four lakes". This was accepted by the foremost etymologist of the time, PW Joyce, as the definitive origin of the name; although Joyce noted there was no evidence to suggest that these lakes ever existed in the area.
It is today believed that the first part of the name derives from the Old Irish word cethrae ("animals, cattle, herds, flocks"), which is related to ceathar ("four") and therefore signified "four-legged". The second part of the name is the ending -lach, meaning that "Ceatharlach" referred to a "place of cattle or herds". As the local dialect of Irish evolved, the "th" phoneme became obsolete. Consequently, by the 13th century the pronunciation of the name would have been much closer to its modern anglicised form. Surviving texts from the 15th and 16th centuries which spell the name as "Carelagh" and "Kerlac" seem to reflect this change in pronunciation.
Geography and subdivisions
Carlow is the second-smallest of Ireland's 32 counties by area, and the third-smallest in terms of population. It is the second-smallest of Leinster's 12 counties in both size and population. Carlow is landlocked and bordered by five counties – Kilkenny to the west, Wicklow to the east, Wexford to the southeast, and Laois and Kildare to the north. Carlow town is both the county town and largest settlement, and is situated on the River Barrow in the north of the county approximately 80 km (50 mi) from Waterford and 85 km (53 mi) from Dublin.

Physical geography
Carlow's southern, western and eastern boundaries are demarcated by the county's three principal geographic features – the River Barrow, the River Slaney and the Blackstairs Mountains – which are all European Union designated Special Areas of Conservation (SACs). The county is divided into six physiographic regions – the Barrow Valley, Castlecomer Plateau, Nurney Ridge and Blackstairs Mountains, as well as the Tullow Lowlands and Southern Wedge, which are grouped together as an "Intermediate Region". The county is generally rural in nature and has a population density of 63 people per km2, with the majority of the population living within the Barrow Valley.
The River Barrow, at 192 km (119 mi) in length, is Ireland's second longest river. The river cuts out a low-lying valley as it traverse through the county, and much of the county is drained by the Barrow and its tributaries. The most prominent tributary of the Barrow in the area is the Burren River, which rises at Mount Leinster and flows through the county for 39 km (24 mi) before joining the Barrow at Carlow town. The east and northeast of the county are drained by the River Slaney and its tributaries – the River Derreen, which flows through Hacketstown and Tullow, and the River Derry, which rises at Eagle Hill south of Hacketstown and forms the border between Carlow and Wexford before joining the Slaney at Bunclody.
As of 2017, there is a total of 8,403 ha (20,764 acres) of forest cover in the county, representing 9.4% of total land area. This is below the national average of 11% forest cover and represents just 1.1% of the national forest total. The majority of the county's forests are located in upland areas, namely the Blackstairs Mountains in the east of the county, and the Castlecomer Plateau in the west of the county. Conifers are primarily grown in these areas and constitute 69.9% of all forest cover within the county. Due to the high quality of land in the lowlands and southern wedge, the area under forest is low, as most of the land is used for agricultural purposes. Some of the oldest deciduous trees in the county are found in the yew grove at the Huntington Gardens, which were planted by the Esmonde family over 500 years ago. Other notable woodland areas include the Oak Park Forest, which is a ca. 123 acre mixed forest of beech, oak, Scots pine, silver fir, larch and sycamore; the Altamont Gardens and the Barrow Way.

Climate
Carlow is in a maritime temperate oceanic region according to Köppen climate classification. It experiences cool winters, mild humid summers, and a lack of temperature extremes. Met Éireann records climate data for Carlow from their station at Oak Park, situated at 61 m (200 ft) above sea level. The coldest month is February, with an average daily minimum temperature of 2.1 °C (36 °F), and the hottest month is July, with an average daily maximum temperature of 21.3 °C (70 °F). The driest months are April and May, with 45 mm (2 in) and 50 mm (2 in) of rain respectively. The wettest month is November, with 98 mm (4 in) of rain on average. Humidity is high year round and rainfall is evenly distributed throughout the year. A number of synoptic stations which record rainfall are located throughout the county. The driest area of the county is at Tullow, which receives 840 mm (33 in) of rainfall per year, and the Blackstairs Mountains are the wettest area, receiving 1,446 mm (57 in) of rainfall per year.
While Carlow is often marketed as being part of the Sunny Southeast alongside Wexford and Waterford, due to its inland location it does not typically benefit from the elevated sunshine hours observed in the coastal areas of those counties. However, it does experience significantly higher average temperatures and lighter winds during the summer months due to its sheltered location. This was exemplified during the 2018 summer heat wave, when Oak Park was both the hottest and driest location in Ireland.
Geology
The bedrock geology of Carlow consists primarily of granite, which underlies roughly 70% of the county. Following the closure of the Iapetus Ocean approximately 400 Mya, a mountain range formed in the area which was then intruded with magma. This cooled slowly beneath the surface, forming a large granite pluton. The mountains, which were mostly composed of Ordovician seafloor sediments, were eventually eroded away, exposing the granite at the surface. During the Carboniferous, ca. 300 Mya, limestone re-buried this granite, but has also since been eroded away. More resilient Carboniferous period shales and sandstones are preserved in the Castlecomer Plateau, along with significant quantities of coal.

The oldest rocks in the county are the surviving remnants of these Ordovician seafloor sediments (ca. 540 Mya), and are found in a thin belt extending across the east of the county. These sediments were intensely metamorphosed by the heat of the granite into high-grade schists and hornfels. Minerals such as staurolite, andalusite and garnet are commonplace in these older formations.
The soils of the county are mostly derived from glacial till, rather than solid bedrock geology. These typically consist of a mix of clay, sand and gravel. Occasionally glacial melt-water would form a long ridge of sand and gravel known as an esker. One such example is preserved within the county and is a proposed natural heritage area, referred to as the Ballymoon Esker. The north of the county is generally flat, while central and southern Carlow are characterised by an undulating to rolling topography which becomes progressively hillier towards the south and east. The Blackstairs Mountains are the highest and most extensive upland area, with Mount Leinster rising to 794 m (2,605 ft), making it the highest point in both Carlow and Wexford and the seventh highest county top in Ireland.
Baronies
There are seven historic baronies in the county. While baronies continue to be officially defined units, they are no longer used for administrative purposes. The last boundary change of a barony in Carlow was in 1841, when the barony of St. Mullin's was divided into St. Mullin's Lower and St. Mullin's Upper. Their official status is illustrated by Placenames Orders made since 2003, where official Irish names of baronies are listed under "Administrative units". The largest barony in Carlow is Idrone East, at 52,857 acres (214 km2), and the smallest barony is St. Mullin's Upper, at 7,784 acres (32 km2).

Carlow (Ceatharlach)
Forth (Fotharta)
Idrone East (Uí Dhróna Thoir)

Idrone West (Uí Dhróna Thiar)
Rathvilly (Ráth Bhil)
St. Mullin's Lower (Tigh Moling Íochtarac)
St. Mullin's Upper (Tigh Moling Uachtarach)
Civil parishes and townlands
Townlands are the smallest officially defined geographical divisions in Ireland. There are 650 townlands in Carlow, of which 22 are historic town boundaries. These town boundaries are registered as their own townlands and are much larger than rural townlands. The rural townlands of Carlow range from just 1 acre in size (Acuan) to 1,822 acres (Kilbrannish South), with the average size of a townland in the county (excluding towns) being 371 acres.
Towns and villages
Governance and politics
Local government
Local government in County Carlow is governed by the Local Government Acts. There is a single level of local government in the county, with Carlow County Council responsible for local services.
There are 18 councillors on the county council. It is currently divided into three local electoral areas (LEAs), each of which is also a municipal district: Carlow (7), Muine Bheag (5) and Tullow (6).
Council elections are held every 5 years, with the next election due to be held in June 2029. The 2024 Carlow local election had a voter turnout of 47.5%, a decrease of 1.9% on the 2019 local election. The highest turnout was at Muine Bheag (51.3%) and the lowest was at Carlow (43.5%).
As was the case in much of Ireland, Fianna Fáil and Fine Gael emerged as the two dominant parties in the 2024 local elections, holding 11 of the 18 seats between them. Sinn Féin hold 2 seats, the Labour Party, People Before Profit, and Independent Ireland hold 1 seat each, and there are 2 independents.
As part of the Southern Region (NUTS II Region), the council has two representatives on the Southern Regional Assembly, where it is part of the South-East strategic planning area (NUTS III Region).
Former districts
It was formerly divided into the rural districts of Baltinglass No. 2, Carlow, and Idrone, and the urban district of Carlow. The rural districts were abolished in 1925. Bagnelstown (Muine Bheag) and Tullow, within the former rural district of Carlow, had town commissioners. The town of Tullow was later disestablished as separate area. In 2002, the urban district of Carlow and the town commissioners of Muinebheag became town councils. All town councils in Ireland were abolished in 2014.
National elections
Carlow is part of the Dáil constituency of Carlow–Kilkenny which returns 5 TDs. The constituency has been in existence since the 1948 general election.
Prior to 1801, the county was represented in the Irish House of Commons through the constituencies of County Carlow, Carlow and the bishop's borough of Old Leighlin, each of which returned two MPs. Following the Act of Union, the county was represented in Westminster through the County Carlow constituency, which returned two MPs (reduced to one under the Redistribution of Seats Act 1885. It was this constituency that gave Carlow representation in the First Dáil, convened in 1919.
It was part of the Dáil constituency of Carlow-Kilkenny from 1921 to 1937. Between 1937 and 1948 the county was divided, with the northern half of the county part of the Carlow-Kildare constituency, and the southern half joining the Wexford constituency. Since 1948, the county has again been joined with Kilkenny for national elections as Carlow–Kilkenny. From 1997 to 2020, a portion of the county was in the Wicklow, rejoining the rest of Carlow at the 2020 general election.
Carlow is part of the European Parliament constituency of South (5 seats).
History
The area of present-day Carlow has been inhabited for thousands of years, and the county has perhaps the highest concentration of megalithic monuments per square kilometre in Ireland. Numerous standing stones, bullauns and cairns mark the landscape. Carlow is nicknamed the "Dolmen County", reflecting the abundance of dolmens found within its borders, of which the Brownshill Dolmen is reputed to be the largest in Europe. The historic clan territories of the county included Uí Drona (O'Ryan), Fothairt Feadh (O'Nolan), Uí Ceinnselaig (Kinsella), Dál Coirpri Cliach (Kerwick), Uí Bairrche Magh dá chonn (Kearney), Uí Felmeda Tuaidh (O'Garvey) and Uí Bairrch Maige hAilbe (O'Gorman). As Carlow contained both the navigable river Barrow as well as the Slighe Cualann (one of the key arterial roads leading to Tara), control of the area was vital to the claim of any prospective king of Leinster, and the area was much fought over. By the 11th century the Mac Murchada branch of the Uí Ceinnselaig dynasty had firmly established themselves as the Kings of Leinster.
Emergence as a County
With the exception of a short-lived Norse–Gael settlement near St. Mullin's in the 9th century, the area remained under the control of the Kingdom of Leinster until the early 13th century. Following the Norman conquest, the "Borough of Carlow" was founded in July 1210, and formed part of the Norman palatine county of Leinster. This was later divided and the independent Liberty of Carlow was established in 1247. At that time the county was over three times larger than it is today, covering approximately 724,000 acres (2,930 km2) and encompassing the majority of the old Diocese of Leighlin, extending to and including the coastal area around Arklow.
The modern county boundary was shaped by the Gaelic Resurgence from the 14th to 16th centuries. During this period, Carlow was part of the patrimony of the Anglo-Norman Butler dynasty; however Art MacMurrough-Kavanagh, the ascendant King of Leinster, controlled more than half of the liberty. He was paid by the Anglo-Normans for his "services" in keeping the roads and trade routes of the area free of bandits, but in reality this amounted to nothing more than rent exacted by MacMurrough-Kavanagh as recognition of his sovereignty over the area. His authority was so absolute that the MacMurrough-Kavanagh's retained control over large portions of the county for centuries, despite radical political changes. In the late 15th-century, James Butler, the 9th Earl of Ormond, purchased land within the county to give to his heirs, rather than enter into conflict with the dynasty. Descendants of the King of Leinster are still in possession of their ancestral home of Borris House to this day.
The informal alliance between the Kingdom of Leinster and the Anglo-Normans remained the status quo for decades, as it kept the peace and made both sides immensely wealthy. Cognisant of the political landscape, the Anglo-Normans began to marry into Gaelic families and adapt to native customs, forging alliances with Irish kingdoms to gain the upper hand over their fellow Anglo-Norman rivals. In a bid to halt the decline of English authority in the region, the crown made Carlow the capital of the Lordship of Ireland from 1361 until 1374, just 13 km (8.1 mi) north of MacMurrough-Kavanagh's permanent residence at Leighlin.
Large areas on the northern and eastern fringes of the Liberty of Carlow gradually fell completely to the O'Moores, O'Byrnes and other chiefdoms. Consequently, when the Tudors reconquered these areas in the mid 16th century ownership was not reverted to the Anglo-Normans of Carlow but was instead granted to settlers from Britain. Carlow retained its Irish Sea border, though control of this land became disputed with the ruling chiefs of the area who were petitioning for their own shire. These areas were eventually given over to County Wicklow in 1606. The present-day boundary of Carlow therefore represents the core Norman holdings in the area which had persisted since the 12th century, propped up by the Caomhánach dynasty.
Early modern history
Following the Irish Confederate Wars in the 1650s, the great majority of Gaelic Irish and Anglo-Norman landowners were dispossessed, and their lands were granted to English soldiers who took part in the Cromwellian conquest. Carlow was one of four counties set aside by the Commonwealth government for the payment of public debt, although much of the land in these counties eventually ended up in the hands of notable regicides, considered "friends of the Republic". These lands were legally deemed to be in the possession of King Charles II following the Restoration, and many dispossessed Irish nobles were able to petition the king and recover their lands. The Cromwellian conquest therefore had a limited impact on Carlow, as both Charles and the Parliament of Ireland had shown leniency to ordinary soldiers who were granted land elsewhere in Ireland, but all regicides were either exiled or executed.
Carlow, along with neighbouring Wexford, saw some of the fiercest fighting of the 1798 Rebellion. The rebellion in Carlow is particularly infamous for the sectarian excesses committed within the county. Prior to the rebellion, United Irishmen member William Farrell had claimed "there was no part of Ireland where a better feeling of friendship existed between both Catholics and Protestants, nor no part where greater numbers of both were blood relations". However, in the wake of the French Revolution, local members of the Orange Order organised into a Yeomanry Cavalry Corps which conducted nightly raids on Catholic and Dissenter homes, often burning them to the ground, in search of weapons and revolutionary literature.
As feelings of persecution and religious division grew amongst the overwhelmingly Catholic populace, local United Irish leader Laurence Griffin lamented "the people of Carlow think of all Protestants as Orangemen". Catholics and non-Anglican Protestants could not vote to effect change, so they eventually joined forces with radical liberal Anglicans to overthrow the Parliament. The Battle of Carlow was one of the opening skirmishes of the rebellion in May 1798, and ended in a crushing defeat for the rebel forces. Months of intimidation and revenge attacks followed, led by Reverend Robert Rochfort of Clogrennan House, who oversaw the unlawful kidnapping, torture and execution of suspected United Irishmen, earning Rochfort the nickname "the slashing parson".
The Irish language was still spoken in Carlow as late as the 1870s.
Revolutionary Period
During the War of Independence, the Carlow Brigade of the Irish Republican Army (IRA) had 6 battalions which operated in the shadow of the Curragh Camp – the British Army's headquarters in Ireland – across Carlow, western Wicklow, southern Kildare and eastern Laois and Kilkenny. The abandoned estate at Duckett's Grove served as both an IRA training camp and the headquarters of the Carlow Brigade from 1919 to 1922.
Plagued by poor supply-lines and hindered by a heavy Royal Irish Constabulary (RIC) presence, the Carlow Brigade was one of the least active of the war and mostly specialised in delaying tactics such as blocking roads, destroying bridges and intercepting mail. The brigade carried out a botched ambush near Ballymurphy in April 1921, with the loss of 12 members (4 killed and 8 captured) and vital munitions, after which no further active engagements with either the RIC or British Army were attempted.