Editing County Dublin (section)

==Geography and subdivisions==
{{See also|List of mountains and hills of County Dublin|List of rivers of County Dublin}}
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[[File:Skerries Sunset.jpg|thumb|Sunset over [[Skerries, Dublin|Skerries]]]]
Dublin is the [[List of Irish counties by area|third smallest]] of Ireland's 32 counties by area, and the largest in terms of population. It is the third-smallest of Leinster's 12 counties in size and the largest by population. Dublin shares a border with three counties – [[County Meath|Meath]] to the north and west, [[County Kildare|Kildare]] to the west and [[County Wicklow|Wicklow]] to the south. To the east, Dublin has an [[List of Irish counties by coastline|Irish Sea coastline]] which stretches for {{convert|155|km|mi}}.<ref>{{cite web|url=https://www.fingal.ie/council/service/coastal-walks-0|title=Coastal Walks|work=Fingal County Council|access-date=8 November 2020|archive-date=5 November 2020|archive-url=https://web.archive.org/web/20201105022604/https://www.fingal.ie/council/service/coastal-walks-0|url-status=live}}</ref><ref>{{cite web|url=https://dlrcoco.citizenspace.com/masterplanning/sandycove-and-bullock-harbour-masterplan-consultat/supporting_documents/Bullock%20and%20Sandycove%20Harbours%20Draft%20Masterplan%202019.pdf|title=Bullock and Sandycove Harbours Draft Masterplan|work=DLRCoCo|access-date=8 November 2020|archive-date=11 November 2020|archive-url=https://web.archive.org/web/20201111120337/https://dlrcoco.citizenspace.com/masterplanning/sandycove-and-bullock-harbour-masterplan-consultat/supporting_documents/Bullock%20and%20Sandycove%20Harbours%20Draft%20Masterplan%202019.pdf|url-status=live}}</ref>

Dublin is a topographically varied region. The city centre is generally very low-lying, and many areas of coastal Dublin are at or near sea-level. In the south of the county, the topography rises steeply from sea-level at the coast to over {{convert|500|m|ft}} in just a few kilometres. This natural barrier has resulted in densely populated coastal settlements in [[Dún Laoghaire–Rathdown]] and westward urban sprawl in [[South Dublin]]. In contrast, [[Fingal]] is generally rural in nature and much less densely populated than the rest of the county. Consequently, Fingal is significantly larger than the other three local authorities and covers about 49.5% of County Dublin's land area. Fingal is also perhaps the flattest region in Ireland, with the low-lying [[Naul Hills]] rising to a maximum height of just {{convert|176|m|ft}}.<ref>{{cite web|url=http://www.fingalcoco.ie/minutes/meeting_doc.aspx?id=20716|title=Fingal County Council, 2002|access-date=27 November 2009|url-status=dead|archive-url=https://web.archive.org/web/20110722161412/http://www.fingalcoco.ie/minutes/meeting_doc.aspx?id=20716|archive-date=22 July 2011}}</ref>

Dublin is bounded to the south by the [[Wicklow Mountains]]. Where the mountains extend into County Dublin, they are known locally as the Dublin Mountains (''Sléibhte Bhaile Átha Cliath''). [[Kippure]], on the Dublin–Wicklow border, is the county's highest mountain, at {{convert|757|m|ft}} above sea level. Crossed by the [[Dublin Mountains Way]], they are a popular amenity area, with [[Two Rock]], [[Three Rock]], [[Tibradden]], [[Ticknock]], [[Montpelier Hill]], and [[Glenasmole]] being among the most heavily foot-falled hiking destinations in Ireland. Forest cover extends to over {{convert|6,000|ha|acre}} within the county, nearly all of which is located in the Dublin Mountains. With just 6.5% of Dublin under forest, it is the 6th least forested county in Ireland.<ref>{{cite web|url=https://www.agriculture.gov.ie/media/migration/forestry/forestservicegeneralinformation/MainFindings301018.pdf|title=National Forestry Inventory, Third Cycle 2017|work=DAFM|access-date=8 November 2020|archive-date=27 November 2020|archive-url=https://web.archive.org/web/20201127111823/https://www.agriculture.gov.ie/media/migration/forestry/forestservicegeneralinformation/MainFindings301018.pdf|url-status=live}}</ref>

Much of the county is drained by its three major rivers – the [[River Liffey]], the [[River Tolka]] in north Dublin, and the [[River Dodder]] in south Dublin. The Liffey, at {{convert|132|km|mi}} in length, is the 8th longest river in Ireland, and rises near [[Tonduff]] in County Wicklow, reaching the Irish Sea at the [[Dublin Docklands]]. The Liffey cuts through the centre of Dublin city, and the resultant [[Northside, Dublin|Northside]]–[[Southside, Dublin|Southside]] divide is an often used social, economic and linguistic distinction. Notable inlets include the central [[Dublin Bay]], [[Rogerstown Estuary]], the estuary of the Broadmeadow and Killiney Bay, under [[Killiney Hill]]. Headlands include [[Howth Head]], [[Drumanagh]] and the Portraine Shore.<ref>{{cite web|url=https://gsi.geodata.gov.ie/downloads/Geoheritage/Reports/DF001_Portraine_Shore.pdf|title=Portraine Shore – Fingal County Geological Site Report|work=Fingal County Council|access-date=30 November 2023}}</ref> In terms of [[biodiversity]], these estuarine and coastal regions are home to a wealth ecologically important areas. County Dublin contains 11 [[European Union|EU]]-designated [[Special Area of Conservation|Special Areas of Conservation]] (SACs) and 11 [[Special Protection Area]]s (SPAs).<ref>{{cite web|url=https://www.npws.ie/protected-sites|title=Protected Sites in Ireland|work=NPWS|access-date=8 November 2020|archive-date=8 November 2020|archive-url=https://web.archive.org/web/20201108042254/https://www.npws.ie/protected-sites|url-status=live}}</ref>

The bedrock geology of Dublin consists primarily of [[Lower Carboniferous]] limestone, which underlies about two thirds of the entire county, stretching from Skerries to [[Booterstown]]. During the Lower Carboniferous (ca. 340 Mya), the area was part of a warm tropical sea inhabited by an abundance of [[corals]], [[crinoids]] and [[brachiopods]]. The oldest rocks in Dublin are the [[Cambrian]] shales located on Howth Head, which were laid down ca. 500 Mya. Disruption following the closure of the [[Iapetus Ocean]] approximately 400 [[Geologic time scale|Mya]] resulted in the formation of [[granite]].<ref>{{cite web|url=https://www.gsi.ie/documents/Geoschol_Dublin_Geology.pdf|title=Geology of County Dublin|work=geoschol|access-date=8 November 2020|archive-date=15 November 2017|archive-url=https://web.archive.org/web/20171115060015/https://www.gsi.ie/documents/Geoschol_Dublin_Geology.pdf|url-status=live}}</ref> This is now exposed at the surface from the Dublin Mountains to the coastal areas of Dún Laoghaire. 19th-century [[Lead]] extraction and smelting at the [[Ballycorus Leadmines]] caused widespread [[lead poisoning]], and the area was once nicknamed "Death Valley".<ref>Dún Laoghaire–Rathdown County Council, p. 10.</ref>

===Climate===
[[File:IMG Kippure0232w.jpg|thumb|left|At an elevation of {{convert|757|m|ft|abbr=off}}, [[Kippure]] is the highest point in the county]]
[[File:Sandycove, Summer 2013.jpg|thumb|right|Summertime bathers at [[Sandycove]]]]
[[File:Snow in Killiney, Dublin (2010).jpg|thumb|right|December snow at [[Killiney]]]]
Dublin is in a maritime [[temperate]] [[oceanic climate|oceanic]] region according to [[Köppen climate classification]]. Its climate is characterised by cool winters, mild humid summers, and a lack of temperature extremes. [[Met Éireann]] have a number of weather stations in the county, with its two primary stations at [[Dublin Airport]] and [[Casement Aerodrome]].

Annual temperatures typically fall within a narrow range. In [[Merrion Square]], the coldest month is February, with an average minimum temperature of {{convert|4.1|C|F|abbr=on}}, and the warmest month is July, with an average maximum temperature of {{convert|20.1|C|F|abbr=on}}. Due to the [[urban heat island]] effect, Dublin city has the warmest summertime nights in Ireland. The average minimum temperature at Merrion Square in July is {{convert|13.5|C|F|abbr=on}}, similar to [[London]] and [[Berlin]], and the lowest July temperature ever recorded at the station was {{convert|7.8|C|F|abbr=on}} on 3 July 1974.<ref>{{cite web|url=https://www.met.ie/climate/available-data/historical-data|title=Historical Data: DUBLIN (MERRION SQUARE) – Station No. 3923|publisher=Met Éireann|access-date=9 June 2022|archive-date=24 June 2021|archive-url=https://web.archive.org/web/20210624195529/https://www.met.ie/climate/available-data/historical-data|url-status=live}}</ref><ref>{{cite web|url=http://eca.knmi.nl/utils/mapserver/climatology.php#bottom|title=Climatological Information for Merrion Square, Ireland|publisher=European Climate Assessment & Dataset|access-date=8 November 2020|archive-date=30 August 2012|archive-url=https://web.archive.org/web/20120830134927/http://eca.knmi.nl/utils/mapserver/climatology.php#bottom|url-status=live}}</ref> At Dublin Airport, the driest month is February with {{convert|48.8|mm|0|abbr=on}} of rainfall, and the wettest month is November, with {{convert|79.0|mm|0|abbr=on}} of rain on average.

As the prevailing wind direction in Ireland is from the south and west, the Wicklow Mountains create a [[rain shadow]] over much of the county. Dublin's sheltered location makes it the driest place in Ireland, receiving only about half the rainfall of the west coast. [[Ringsend]] in the south of Dublin city records the lowest rainfall in the country, with an average annual precipitation of {{convert|683|mm|0|abbr=on}}. The wettest area of the county is the [[Glenasmole|Glenasmole Valley]], which receives {{convert|1,159|mm|0|abbr=on}} of rainfall per year. As a temperate coastal county, snow is relatively uncommon in lowland areas; however, Dublin is particularly vulnerable to heavy snowfall on rare occasions where cold, dry easterly winds dominate during the winter.<ref>{{cite web |url=http://www.met.ie/climate/temperature.asp |title=Temperature – Climate |publisher=Met Éireann – The Irish Meteorological Service Online |date=2 January 1979 |access-date=20 August 2010 |archive-date=7 January 2019 |archive-url=https://web.archive.org/web/20190107003129/https://www.met.ie/climate/temperature.asp%20 |url-status=live }}</ref>

During the late summer and early autumn, Dublin can experience Atlantic storms, which bring strong winds and torrential rain to Ireland. Dublin was the county worst-affected by [[Hurricane Charley (1986)|Hurricane Charley]] in 1986. It caused severe flooding, especially along the River Dodder, and is reputed to be the worst flood event in Dublin's history. Rainfall records were shattered across the county. Kippure recorded {{convert|280|mm|0|abbr=on}} of rain over a 24-hour period, the greatest daily rainfall total ever recorded in Ireland. The government allocated [[Irish pound|IR£]]6,449,000 (equivalent to US$20.5 million in 2020) to repair the damage wrought by Charley.<ref>{{cite web|date=8 March 1990 |title=Storm and Flood Damage: Motion – Seanad Éireann |publisher=Office of the Houses of the Oireachtas |access-date=26 October 2008 |url=http://historical-debates.oireachtas.ie/S/0124/S.0124.199003080005.html |url-status=dead |archive-url=https://web.archive.org/web/20110607120811/http://historical-debates.oireachtas.ie/S/0124/S.0124.199003080005.html |archive-date=7 June 2011 }}</ref> The two reservoirs at Bohernabreena in the Dublin Mountains were upgraded in 2006 after a study into the impact of Hurricane Charley concluded that a slightly larger storm would have caused the reservoir dams to burst, which would have resulted in catastrophic damage and significant loss of life.

===Offshore islands===
In contrast with the [[Wild Atlantic Way|Atlantic Coast]], the east coast of Ireland has relatively few islands. County Dublin has one of the highest concentrations of islands on the Irish east coast. Colt Island, St. Patrick's Island, Shenick Island and numerous smaller [[islets]] are clustered off the coast of Skerries, and are collectively known as the "Skerries Islands Natural Heritage Area". Further out lies [[Rockabill]], which is Dublin's most isolated island, at about {{convert|6|km|mi}} offshore. [[Lambay Island]], at {{convert|250|ha|acre}}, is the largest island off Ireland's east coast and the easternmost point of County Dublin. Lambay supports one of the largest seabird colonies in Ireland and, curiously, also supports a population of non-native [[Red-necked wallaby|Red-necked wallabies]].<ref>{{cite web |title=East coast – Knockbane (Hill), Lambay Island |url=https://mountainviews.ie/summit/1370/ |website=MountainViews.ie |access-date=3 June 2020 |quote=Height: 126m OS 1:50k Mapsheet: 43 Grid Reference: O31600 51000 |archive-date=3 June 2020 |archive-url=https://web.archive.org/web/20200603091908/https://mountainviews.ie/summit/1370/ |url-status=live }}</ref> To the south of Lambay lies a smaller island known as [[Ireland's Eye]] – the result of a mistranslation of the island's Irish name by invading [[Vikings]].

[[Bull Island]] is a man-made island lying roughly parallel to the shoreline which began to form following the construction of the [[Bull Wall]] in 1825. The island is still growing and is currently {{convert|5|km|mi}} long and {{convert|0.8|km|mi}} wide. In 1981, North Bull Island (''Oileán an Tairbh Thuaidh'') was designated as a [[UNESCO]] biosphere.<ref>{{Cite web|title=North Bull Island|website=[[Ramsar Convention|Ramsar]] Sites Information Service|url=https://rsis.ramsar.org/ris/406|access-date=25 April 2018|archive-date=24 May 2018|archive-url=https://web.archive.org/web/20180524082454/https://rsis.ramsar.org/ris/406|url-status=live}}</ref>
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===Subdivisions===
[[File:EircodeDublin.svg|thumb|Dublin's postal subdivisions after the implementation of [[Eircode]]s. They include the city's historic postal districts and the newer A and K Dublin codes. ]]
[[File:IrelandBaronies1899Map (Dublin cropped).png|thumb|upright|The baronies of County Dublin]]
{{Main|List of subdivisions of County Dublin}}
{{See also|List of Dublin postal districts}}

For statistical purposes at European level, the county as a whole forms the Dublin Region – a [[Nomenclature of Territorial Units for Statistics|NUTS III]] entity – which is in turn part of the [[Eastern and Midland Region]], a NUTS II entity. Each of the local authorities have representatives on the Eastern and Midland Regional Assembly.

====Baronies====
{{See also|List of baronies of Ireland}}
There are ten historic [[Barony (Ireland)|baronies]] in the county.<ref>[https://www.logainm.ie/en/s?txt=in:100002&cat=BAR Placenames Database of Ireland] {{Webarchive|url=https://web.archive.org/web/20210121202131/https://www.logainm.ie/en/s?txt=in:100002&cat=BAR |date=21 January 2021 }} – Baronies.</ref> While baronies continue to be officially defined units, they ceased to have any administrative function following the [[Local Government (Ireland) Act 1898|Local Government Act 1898]], and any changes to county boundaries after the mid-19th century are not reflected in their extent. The last boundary change of a barony in Dublin was in 1842, when the barony of Balrothery was divided into Balrothery East and Balrothery West. The largest recorded barony in Dublin in 1872 was Uppercross, at {{convert|39,032|acre|km2}}, and the smallest barony was Dublin, at {{convert|1,693|acre|km2}}.
{| class="wikitable sortable collapsible nowrap" style="font-size: 100%; text-align: right; display:inline-table"
|+ '''Historic baronies of County Dublin'''
|-
! Barony !! Irish name !! Area<ref>{{cite web|url=https://www.townlands.ie/dublin/|title=Townlands in Co. Dublin|work=townlands.ie|access-date=29 June 2021|archive-date=29 June 2021|archive-url=https://web.archive.org/web/20210629075701/https://www.townlands.ie/dublin/|url-status=live}}</ref><br /><small>(acres)</small><br />
|-
| style="text-align: left;" | [[Balrothery East]] || ''Baile an Ridire Thoir'' || 30,229
|-
| style="text-align: left;" | [[Balrothery West]] || ''Baile an Ridire Thiar'' || 24,818
|-
| style="text-align: left;" | [[Castleknock (barony)|Castleknock]] || ''Caisleán Cnucha'' || 22,911
|-
| style="text-align: left;" |[[Coolock (barony)|Coolock]] || ''An Chúlóg'' || 29,664
|-
| style="text-align: left;" | [[Dublin (barony)|Dublin]] || ''Baile Átha Cliath'' || 1,693
|-
| style="text-align: left;" | [[Dublin|Dublin City]] || ''Cathair Baile Átha Cliath'' || 3,736
|-
| style="text-align: left;" | [[Nethercross]] || ''An Chrois Íochtarach'' || 22,616
|-
| style="text-align: left;" | [[Newcastle (County Dublin barony)|Newcastle]] || ''An Caisleán Nua'' || 21,238
|-
| style="text-align: left;" | [[Rathdown (County Dublin barony)|Rathdown]] || ''Ráth an Dúin'' || 29,974
|-
| style="text-align: left;" | [[Uppercross]]|| ''An Chrois Uachtarach'' || 39,032
|}

====Townlands====
[[File:Three Rock Mountain Southern Tor.jpg|thumb|Summit of [[Three Rock Mountain|Three Rock]] in the [[Dublin Mountains Way|Dublin Mountains]], within the townland of [[Ticknock]]]]
{{main|List of townlands of County Dublin}}
Townlands are the smallest officially defined geographical divisions in Ireland. There are 1,090 townlands in Dublin, of which 88 are historic town boundaries. These town boundaries are registered as their own townlands and are much larger than rural townlands. The smallest rural townlands in Dublin are just 1 acre in size, most of which are offshore islands (''Clare Rock Island, Lamb Island, Maiden Rock, Muglins, Thulla Island''). The largest rural townland in Dublin is 2,797 acres (''Caastlekelly''). The average size of a townland in the county (excluding towns) is 205 acres.

====Towns and suburbs====
{{main|List of towns and villages in County Dublin}}

====Urban and rural districts====
Under the [[Local Government (Ireland) Act 1898]], County Dublin was divided into [[urban and rural districts (Ireland)|urban districts]] of [[Blackrock, Dublin|Blackrock]], [[Clontarf, Dublin|Clontarf]], [[Dalkey]], [[Drumcondra, Clonliffe and Glasnevin]], [[Killiney and Ballybrack]], [[Dún Laoghaire|Kingstown]], [[New Kilmainham]], [[Pembroke, Dublin|Pembroke]], and [[Rathmines and Rathgar]], and the [[rural district (Ireland)|rural districts]] of [[Balrothery]], Celbridge No. 2, North Dublin, [[Rathdown (County Dublin barony)|Rathdown]], and South Dublin.<ref>{{cite book |last=Clancy |first=John Joseph|author-link=J. J. Clancy (North Dublin MP)|title=A handbook of local government in Ireland: containing an explanatory introduction to the Local Government (Ireland) Act, 1898: together with the text of the act, the orders in Council, and the rules made thereunder relating to county council, rural district council, and guardian's elections: with an index|url=https://archive.org/details/handbookoflocalg00clan/page/427/mode/2up |page=427 |year=1899|publisher=Sealy, Bryers and Walker|location=Dublin }}</ref>

Howth, formerly within the rural district of Dublin North, became an urban district in 1919.<ref>{{cite web |title=1926 Census: Table 9: Population, Area and Valuation of urban and rural districts and of all towns with a population of 1,500 inhabitants or over, showing particulars of town and village population and of the number of persons per 100 acres |url=https://www.cso.ie/en/media/csoie/census/census1926results/volume1/C_1926_V1_T9.pdf |archive-url=https://web.archive.org/web/20160427074421/http://www.cso.ie/en/media/csoie/census/census1926results/volume1/C_1926_V1_T9.pdf |archive-date=2016-04-27 |url-status=live |publisher=Central Statistics Office |pages=20–21 |access-date=28 September 2022}}</ref> Kingstown was renamed Dún Laoghaire in 1920.<ref>{{Cite web|date=2020-07-07|title=What's in a name? Dun Leary – Kingstown – Dún Laoghaire|url=https://www.dlrcoco.ie/en/news/general-news/what%E2%80%99s-name-dun-leary-%E2%80%93-kingstown-%E2%80%93-d%C3%BAn-laoghaire|url-status=live|archive-url=https://web.archive.org/web/20210127034536/https://www.dlrcoco.ie/en/news/general-news/what%E2%80%99s-name-dun-leary-%E2%80%93-kingstown-%E2%80%93-d%C3%BAn-laoghaire|archive-date=2021-01-27|access-date=2021-05-29|website=Dún Laoghaire–Rathdown County Council|language=en}}</ref> The rural districts were abolished in 1930.<ref>{{cite ISB|title=[[Local Government (Dublin) Act 1930]]|section=82|stitle=Abolition of rural district councils in the County|year=1930|num=27|parl=ifs|date=17 July 1930}}</ref>

[[Balbriggan]], in the rural district of Balrothery, had [[town commissioners]] under the Towns Improvement (Ireland) Act 1854. This became a town council in 2002.<ref>{{cite ISB|year=2001|num=37|title=[[Local Government Act 2001]]|schedno=6|stitle=Local Government Areas (Towns)|date=21 July 2001|access-date=3 August 2022}}</ref> In common with all town councils, it was abolished in 2014.

The urban districts were gradually absorbed by the city of Dublin, except for four coastal districts of Blackrock, Dalkey, Dún Laoghaire, and Killiney and Ballybrack, which formed the [[borough of Dún Laoghaire]] in 1930.<ref>{{cite ISB|title=Local Government (Dublin) Act 1930|section=3|stitle= Formation of the Borough of Dun Laoghaire|year=1930|num=27|parl=ifs|date=17 July 1930}}</ref>

====County boundaries====
{| class="wikitable"
|+ Changes to county boundaries
|-
! Year !! Changes
|-
| 1900 || Abolition of the urban districts of [[Clontarf, Dublin|Clontarf]], [[Drumcondra, Clonliffe and Glasnevin]] and [[New Kilmainham]] and transfer with the surrounding areas to the city<ref>[[Dublin Corporation Act 1900]] ([[63 & 64 Vict.]] c. cclxiv)</ref>
|-
| 1930 || Abolition of the urban districts of [[Pembroke, Dublin|Pembroke]] and [[Rathmines and Rathgar]], and transfer to the city<ref>{{cite ISB|title=[[Local Government (Dublin) Act 1930]]|section=2|stitle=Inclusion of certain urban districts in the city|year=1930|num=27|parl=ifs|date=17 July 1930}}</ref>
|-
| 1931 || Transfer of Drumcondra, Glasnevin, Donnybrook and Terenure to the city<ref>{{cite ISB|title=Local Government (Dublin) Act 1930|section=17|stitle=Inclusion of certain rural areas in the City|year=1930|num=27|parl=ifs|date=17 July 1930}}; {{cite ISB|title=Local Government (Dublin) Act 1930|schedno=1|stitle=Added rural area|year=1930|num=27|parl=ifs|date=17 July 1930}}</ref>
|-
| 1941 || Transfer of Crumlin to the city<ref>{{cite ISB|year=1941|type=prv|num=1|title=Local Government and Public Health Provisional Order Confirmation Act 1941|date=17 July 1941}}</ref>
|-
| 1942 || Abolition of the urban district of [[Howth]], and transfer to the city<ref>{{cite ISB|year=1940|number=21|name=Local Government (Dublin) (Amendment) Act 1940|section=4|stitle=Inclusion of Howth urban district in Dublin city|date=10 July 1940}}; {{cite ISB|year=1942|type=si|number=372|name=Local Government (Dublin) (Amendment) Act 1940 (Appointed Day) Order 1942|date=20 August 1942}}</ref>
|-
| 1953 || Transfer of Finglas, Coolock and Ballyfermot to the city<ref>{{cite ISB|year=1953|type=prv|num=1|title=Local Government Provisional Order Confirmation Act 1953|date=28 March 1953|schedule=y |access-date=13 September 2013 |archive-date=7 January 2019 |archive-url=https://web.archive.org/web/20190107002751/http://www.irishstatutebook.ie/1953/en/act/prv/0001/print.html%20 |url-status=live }}</ref>
|-
| 1985 || Transfer of Santry and Phoenix Park to the city<br />transfer of Howth, Sutton and parts of Kilbarrack including Bayside from the city<ref>{{cite ISB|section=10|year=1985|num=7|stitle=Alteration of boundaries of Dublin City and County|title=Local Government (Reorganisation) Act 1985|date=3 April 1985|access-date=17 August 2021}}; {{cite ISB|type=si|year=1985|num=129|title=Local Government (Reorganisation) Act (Commencement) (No. 2) Order 1985|date=8 May 1985|access-date=17 August 2021}}</ref>
|-
| 1994 || Abolition of County Dublin and the borough of Dún Laoghaire on the establishment of new counties
|}

====Counties and the city====
[[File:Co-Dublin-COA.jpg|thumb|right|Remnant of the county's historic [[Armorial of Ireland#Counties|coat of arms]] on [[Parnell Square]]]]
[[File:Map of the Dublin Region2.PNG|thumb|right|The Dublin Region: 1. [[Dublin|Dublin City]]; 2. [[Dún Laoghaire–Rathdown]]; 3. [[Fingal]]; 4. [[South Dublin]].]]
The city of [[Dublin]] had been administered separately since the 13th century. Under the [[Local Government (Ireland) Act 1898]], the two areas were defined as the administrative county of Dublin and the county borough of Dublin, with the latter in the city area.

In 1985, County Dublin was divided into three electoral counties: Dublin–Belgard to the southwest (South Dublin from 1991), Dublin–Fingal to the north (Fingal from 1991), and Dún Laoghaire–Rathdown to the southeast.<ref>{{cite ISB|year=1985|num=7|section=12|stitle=Establishment of Dublin Electoral Counties|title=Local Government (Reorganisation) Act 1985|date=3 April 1985|access-date=9 December 2021|archive-url=https://web.archive.org/web/20110605130709/http://www.irishstatutebook.ie/1985/en/act/pub/0007/sec0012.html |archive-date=5 June 2011}}</ref><ref>{{cite ISB|type=si|year=1985|num=133|title=Dublin Electoral Counties Order 1985|date=10 May 1985|access-date=13 December 2021|archive-url=https://web.archive.org/web/20101111023846/http://www.irishstatutebook.ie/1985/en/si/0133.html |archive-date=11 November 2010}}</ref><ref>{{cite ISB|year=1991|num=11|section=26|stitle=Amendment of Local Government (Reorganisation) Act 1985|title=Local Government Act 1991 |date=18 May 1991|access-date=9 December 2021}}</ref>

On 1 January 1994, under the [[Local Government (Dublin) Act 1993]], the County Dublin ceased to exist as a local government area, and was succeeded by the counties of [[Dún Laoghaire–Rathdown]], [[Fingal]] and [[South Dublin]], each coterminous (with minor boundary adjustments) with the area of the corresponding electoral county.<ref>{{cite ISB|year=1993|num=31|title=[[Local Government (Dublin) Act 1993]]|section=9}}</ref><ref>{{cite ISB|year=1993|num=31|section=2|title=[[Local Government (Dublin) Act 1993]]|archive-url=https://web.archive.org/web/20110605192657/http://www.irishstatutebook.ie/1993/en/act/pub/0031/print.html |archive-date=5 June 2011|quote='the county', in relation to any time before the establishment day, means the administrative county of Dublin.}}</ref> In discussing the legislation, [[Avril Doyle]] [[Teachta Dála|TD]] said, "The Bill before us today effectively abolishes County Dublin, and as one born and bred in these parts of Ireland I find it rather strange that we in this House are abolishing County Dublin. I am not sure whether Dubliners realise that that is what we are about today, but in effect that is the case."<ref>{{cite web|url=https://www.oireachtas.ie/en/debates/debate/dail/1993-11-03/speech/62/|title=Local Government (Dublin) Bill, 1993: Second Stage|date=3 November 1993|archive-url=https://web.archive.org/web/20050319103229/http://www.oireachtas-debates.gov.ie/D/0435/D.0435.199311030007.html |archive-date=19 March 2005 }}</ref>

Although the [[Electoral Commission (Ireland)|Electoral Commission]] should, as far as practicable, avoid breaching county boundaries when recommending [[Dáil constituencies]], this does not include the boundaries of a city or the boundary between the three counties in Dublin.<ref>{{cite ISB|year=2022|num=30|section=57|stitle=Constituency review reports|title=[[Electoral Reform Act 2022]]|date=25 July 2022|access-date=4 September 2023}}</ref> There is also still a [[sheriff#Republic of Ireland|sheriff]] appointed for County Dublin.<ref>{{cite press release |last1=Nick |first1=Callan |title=Government makes appointments to Sheriff posts |url=https://merrionstreet.ie/en/News-Room/Releases/Government_makes_appointments_to_Sheriff_posts.html |website=merrionstreet.ie |access-date=11 July 2019 |language=en |date=30 November 2018 |archive-date=11 July 2019 |archive-url=https://web.archive.org/web/20190711165847/https://merrionstreet.ie/en/News-Room/Releases/Government_makes_appointments_to_Sheriff_posts.html |url-status=live }};
{{cite web |last1=Hyland |first1=Paul |title=Explainer: Who and what are Ireland's sheriffs? |url=https://www.thejournal.ie/explainer-irelands-sheriffs-541570-Aug2012/ |website=TheJournal.ie |access-date=11 July 2019 |language=en |date=5 August 2012 |archive-date=11 July 2019 |archive-url=https://web.archive.org/web/20190711155747/https://www.thejournal.ie/explainer-irelands-sheriffs-541570-Aug2012/ |url-status=live }};
{{cite web |title=Role of County Registrar |url=http://www.courts.ie/offices.nsf/0/8980B57008F0A15E802573D0006849DF?OpenDocument |publisher=Courts Service of Ireland |access-date=11 July 2019 |archive-date=1 July 2019 |archive-url=https://web.archive.org/web/20190701153012/http://www.courts.ie/offices.nsf/0/8980B57008F0A15E802573D0006849DF?OpenDocument |url-status=live }};
{{cite news |last1=Sheehan |first1=Maeve |title=Good, bad and ugly side of being the city's sheriff |url=https://www.independent.ie/irish-news/good-bad-and-ugly-side-of-being-the-citys-sheriff-29859088.html |access-date=11 July 2019 |work=Sunday Independent |date=22 December 2013 |language=en |archive-date=11 July 2019 |archive-url=https://web.archive.org/web/20190711165843/https://www.independent.ie/irish-news/good-bad-and-ugly-side-of-being-the-citys-sheriff-29859088.html |url-status=live }}</ref>

The term "County Dublin" is still in common usage. Many organisations and sporting teams continue to organise on a County Dublin basis. The Placenames Branch of the [[Department of Tourism, Culture, Arts, Gaeltacht, Sport and Media]] maintains a [[Placenames Database of Ireland|Placenames Database]] that records all placenames, past and present.<ref>{{cite web|url=https://www.logainm.ie/en/inf/coiste|website=Logainm.ie|title=The Placenames Committee|access-date=14 January 2022|archive-date=15 January 2022|archive-url=https://web.archive.org/web/20220115062637/https://www.logainm.ie/en/inf/coiste|url-status=live}}</ref> County Dublin is listed in the database along with the subdivisions of that county.<ref>{{cite web |title=Baile Átha Cliath/Dublin |url=https://www.logainm.ie/en/100002 |website=Logainm |publisher=[[Government of Ireland]] |access-date=14 January 2022 |archive-date=14 January 2022 |archive-url=https://web.archive.org/web/20220114120638/https://www.logainm.ie/en/100002 |url-status=live }}</ref><ref>{{cite ISB|title=Placenames (Provinces and Counties) Order 2003 |year=2003|date=30 October 2003|type=si|num=519|lang=Irish |access-date=21 December 2019 |archive-date=18 November 2018 |archive-url=https://web.archive.org/web/20181118214710/http://www.irishstatutebook.ie/eli/2003/si/519/made/ga/print |url-status=live }}</ref> It is also used as an address for areas within Dublin outside of the [[List of Dublin postal districts|Dublin postal district system]].<ref>{{cite web |title=Contact Us |url=https://www.fingal.ie/contact-us |website=Fingal County Council |access-date=23 January 2022 |archive-date=23 January 2022 |archive-url=https://web.archive.org/web/20220123141329/https://www.fingal.ie/contact-us |url-status=live }}</ref><ref>{{cite web |title=Contact Us |url=https://www.dlrcoco.ie/en/contact-us |website=Dún Laoghaire–Rathdown County Council |access-date=23 January 2022 |archive-date=23 January 2022 |archive-url=https://web.archive.org/web/20220123141338/https://www.dlrcoco.ie/en/contact-us |url-status=live }}</ref>

For a period in 2020 during the [[COVID-19 pandemic in the Republic of Ireland|COVID-19 pandemic]], to reduce person-to-person contact, government regulations restricted activity to "within the county in which the relevant residence is situated". Within the regulations, the local government areas of "Dún Laoghaire–Rathdown, Fingal, South Dublin and Dublin City" were deemed to be a single county (as were the city and the county of Cork, and the city and the county of Galway).<ref>{{cite ISB|title=Health Act 1947 (Section 31A – Temporary Restrictions) (Covid-19) (No. 2) Regulations 2020|year=2020|type=si|num=206|date=8 June 2020|access-date=10 January 2022}}</ref>

The latest [[Ordnance Survey Ireland]] "Discovery Series" (Third Edition 2005) 1:50,000 map of the Dublin Region, Sheet 50, shows the boundaries of the city and three surrounding counties of the region. Extremities of the Dublin Region, in the north and south of the region, appear in other sheets of the series, 43 and 56 respectively.