| Name | Country | Feature class | Latitude | Longitude | |
|---|---|---|---|---|---|
251  | Lough Derg  Lough Derg | Ireland, Ulster Donegal | lake | N 54° 37′ 10'' | W 7° 52′ 17'' |
| 252 | Lough Dan Loch Dean,Loch Deán,Lough Dan | Ireland, Leinster County Wicklow | lake | N 53° 4′ 4'' | W 6° 16′ 55'' |
| 253 | Lough Cutra Lough Cutra | Ireland, Connacht Galway | lake | N 53° 2′ 8'' | W 8° 46′ 54'' |
| 254 | Lough Currane Loch Luioch,Loch Luíoch,Lough Currane,Lough Leeagh | Ireland, Munster Co Kerry | lake | N 51° 50′ 15'' | W 10° 7′ 57'' |
255  | The Curragh Curragh,The Curragh | Ireland, Leinster Co Kildare | area | N 53° 9′ 10'' | W 6° 50′ 49'' |
| 256 | Lough Cullin Loch Cuilinn,Lough Cullin | Ireland, Connacht County Mayo | lake | N 53° 58′ 12'' | W 9° 10′ 41'' |
| 257 | Lough Cullaunyheeda Lough Cullaunyheeda | Ireland, Munster Clare | lake | N 52° 49′ 14'' | W 8° 46′ 0'' |
| 258 | Lough Cullaun Cullaun,Lough Cullaun | Ireland, Munster Clare | lake | N 52° 57′ 50'' | W 9° 1′ 21'' |
259  | Crumlin Cromghlinn,Crumlin | Ireland, Leinster Dublin City | populated place population 11,294 | N 53° 19′ 17'' | W 6° 18′ 51'' |
| 260 | Cross Lough Cross Lough | Ireland, Connacht County Mayo | lake | N 54° 11′ 51'' | W 10° 4′ 33'' |
| 261 | Lough Corry Lough Corry,Lough Curry | Ireland, Connacht County Roscommon | lake | N 53° 55′ 0'' | W 8° 5′ 0'' |
262  | Cork Contae Chorcai,Contae Chorcaí,Corcaigh,Cork,Cork County,County Cork | Ireland, Munster Cork | second-order administrative division population 399,802 | N 51° 58′ 0'' | W 8° 35′ 0'' |
| 263 | Connemara Conamara,Connemara | Ireland, Connacht Galway | area | N 53° 30′ 0'' | W 9° 45′ 0'' |
| 264 | Connacht Connacht,Cuige Chonnacht,Cúige Chonnacht,Province of Connacht | Ireland, Connacht County Mayo | region | N 53° 40′ 0'' | W 9° 0′ 0'' |
| 265 | Lough Conn Loch Con,Lough Conn | Ireland, Connacht County Mayo | lake | N 54° 2′ 0'' | W 9° 15′ 29'' |
| 266 | Cloonagh Lough Cloonagh Lough | Ireland, Connacht County Roscommon | lake | N 53° 50′ 0'' | W 8° 42′ 0'' |
| 267 | Cloonaghlin Lough Cloonaghlin Lough | Ireland, Munster Co Kerry | lake | N 51° 52′ 27'' | W 10° 1′ 10'' |
| 268 | Cloonacleigha Lough Cloonacleigha Lough | Ireland, Connacht County Sligo | lake | N 54° 4′ 56'' | W 8° 35′ 34'' |
| 269 | Clondalkin Clondalkin,Cluain Dolcain,Cluain Dolcáin,Klondolkin,klandalkyn,Клондолкин,کلاندالکین,კლონდოლკინი | Ireland, Leinster South Dublin | populated place population 14,508 | N 53° 19′ 28'' | W 6° 23′ 50'' |
| 270 | Clonakilty Cloich na Coillte,Clonakilty,Klonakilti,Klounakilti,klwnykyly,Клонакилти,Клоунакилти,کلونیکیلی | Ireland, Munster Cork | populated place population 4,592 | N 51° 37′ 23'' | W 8° 52′ 14'' |
| 271 | Clifden An Clochan,An Clochán,Clifden,Klifden,Клифден,კლიფდენი | Ireland, Connacht Galway | populated place population 1,597 | N 53° 29′ 20'' | W 10° 1′ 8'' |
| 272 | Claremorris Clar Chlainne Mhuiris,Clar Clainne Mhuiris,Claremorris,Clár Chlainne Mhuiris,Clár Clainne Mhuiris,Kl... | Ireland, Connacht County Mayo | populated place population 3,687 | N 53° 43′ 0'' | W 9° 0′ 0'' |
| 273 | Co Clare Clare,Co Clare,Contae an Chlair,Contae an Chláir,County Clare | Ireland, Munster Clare | second-order administrative division population 118,817 | N 52° 50′ 0'' | W 9° 0′ 0'' |
| 274 | Clane Clane,Claonadh,Klejn,klyyn,Клейн,کلئین | Ireland, Leinster Co Kildare | populated place population 7,280 | N 53° 17′ 29'' | W 6° 41′ 21'' |
| 275 | Celbridge Celbridge,Cill Droichid,Selbridzas,Selbridzh,Selbridžas,sai er bu li qi,slbryj,Селбридж,سلبریج,塞爾布里奇 | Ireland, Leinster Co Kildare | populated place population 20,288 | N 53° 20′ 29'' | W 6° 32′ 39'' |
| 276 | Co Cavan Cavan,Co Cavan,Contae an Chabhain,Contae an Chabháin,County Cavan | Ireland, Ulster Cavan | second-order administrative division population 76,176 | N 53° 55′ 0'' | W 7° 15′ 0'' |
| 277 | Cavan An Cabhan,An Cabhán,Cavan,Kavan,Kavanas,Yn Cavan,ka wen,kaebeon,kyaban,kywan,Каван,کیوان,კავანი,キャバン... | Ireland, Ulster Cavan | seat of a second-order administrative division population 6,388 | N 53° 59′ 27'' | W 7° 21′ 38'' |
| 278 | Castledermot Castledermot,Castledermoti nagykeresztek,Diseart Diarmad,Diseart Diarmada,Díseart Diarmada,Kaslderma... | Ireland, Leinster Co Kildare | populated place population 1,475 | N 52° 54′ 32'' | W 6° 50′ 32'' |
| 279 | Castlebar Caislean an Bharraigh,Caisleán an Bharraigh,Castlebar,Kaslbar,Kaslbaras,Kasulbar,ka si er ba,kaeseul... | Ireland, Connacht County Mayo | seat of a second-order administrative division population 12,874, elevation 48m | N 53° 51′ 0'' | W 9° 18′ 0'' |
280  | Rock of Cashel Cashel,Cashel kirkeruin,Castelo de Cashel,Castelo roqueiro,Rocca di Cashel,Rock of Cashel | Ireland, Munster County Tipperary | hill | N 52° 31′ 17'' | W 7° 53′ 16'' |
| 281 | Carrick-on-Suir Carraig na Siuire,Carraig na Siúire,Carrick-on-Suir,Karik on Shur,Karrik-on-Shur,kyrk-an-swyr,Карик ... | Ireland, Munster County Tipperary | populated place population 5,771 | N 52° 20′ 57'' | W 7° 24′ 47'' |
| 282 | Carrick on Shannon Carrick on Shannon,Carrick-On-Shannon,Carrick-on-Shannon,Cora Droma Ruisc,Cora Droma Rúisc,Karik na ... | Ireland, Connacht Leitrim | seat of a second-order administrative division population 3,980 | N 53° 56′ 49'' | W 8° 5′ 24'' |
| 283 | Carrickmacross Carraig Mhacaire Rois,Carraig Mhachaire Rois,Carrickmacross,Karikmakros,Karikmakrosas,Karrikmakross,... | Ireland, Ulster Monaghan | populated place population 5,032 | N 53° 58′ 22'' | W 6° 43′ 8'' |
| 284 | Lough Carra Lough Carra | Ireland, Connacht County Mayo | lake | N 53° 42′ 0'' | W 9° 15′ 0'' |
| 285 | Carlow Carlow,Ceatharlach,Contae Cheatharlach,County Carlow | Ireland, Leinster Carlow | second-order administrative division population 56,932 | N 52° 40′ 0'' | W 6° 50′ 0'' |
| 286 | Lough Caragh Lough Caragh | Ireland, Munster Co Kerry | lake | N 52° 3′ 3'' | W 9° 51′ 48'' |
| 287 | Caher An Chathair,Caher,Cahir,Cathair Dun Iascaigh,Cathair Dún Iascaigh,Kear,Kehr,Ker,Keur,an Chathair,kah... | Ireland, Munster County Tipperary | populated place population 3,593 | N 52° 22′ 37'' | W 7° 55′ 18'' |
| 288 | Cabinteely Caban tSile,Cabinteely,Cábán tSíle,Kabintili,Kabintilis,kbyntyly,kyabintiri,Кабинтили,کبینتیلی,キャビンテ... | Ireland, Leinster Dún Laoghaire-Rathdown | populated place population 10,038 | N 53° 16′ 11'' | W 6° 9′ 38'' |
| 289 | Lough Bunny Lough Bunny | Ireland, Munster Clare | lake | N 53° 1′ 5'' | W 8° 55′ 46'' |
| 290 | Bundoran Bandoran,Bun Dobhrain,Bun Dobhráin,Bundoran,bandorani,Бандоран,Бъндоран,ბანდორანი | Ireland, Ulster Donegal | populated place population 1,963 | N 54° 28′ 40'' | W 8° 16′ 51'' |
| 291 | Bunclody Banklodi,Bun Cloidi,Bun Clóidi,Bunclody,Bunclody-Carrickduff,Newtonbarry,Newtownbarry,ban kou di,ban... | Ireland, Leinster County Wexford | populated place population 1,984 | N 52° 39′ 19'' | W 6° 39′ 12'' |
| 292 | Brittas Lough Brittas,Brittas Lough | Ireland, Leinster County Westmeath | lake | N 53° 34′ 0'' | W 7° 17′ 0'' |
| 293 | Lough Brackley Brackley Lough,Lough Brackley | Ireland, Ulster Cavan | lake | N 54° 8′ 11'' | W 7° 42′ 22'' |
| 294 | Lough Bofin Lough Bofin | Ireland, | lake | N 53° 51′ 0'' | W 7° 56′ 0'' |
| 295 | Lough Bofin Lough Bofin | Ireland, Connacht Galway | lake | N 53° 26′ 0'' | W 9° 27′ 0'' |
| 296 | Lough Boderg Lough Boderg | Ireland, | lake | N 53° 52′ 0'' | W 7° 59′ 0'' |
| 297 | Blasket Islands Blasket,Blasket Islands,Blasket uharteak,Blasket-eilanden,Blasketeilannen,Blasketi saared,Blasketo s... | Ireland, Munster Co Kerry | islands | N 52° 5′ 0'' | W 10° 37′ 0'' |
| 298 | Blanchardstown Baile Bhlainseir,Baile Bhlainséir,Blachardstown,Blancardstaunas,Blanchardstaun,Blanchardstown,Blanča... | Ireland, Leinster Fingal | populated place population 16,511 | N 53° 23′ 17'' | W 6° 22′ 32'' |
| 299 | Blackrock An Charraig Dhubh,Blackrock,Blackrock Dublin,Blakrokas,Blehkrok,Carraig Dubh,blakrwk,blkrak,blqrwq,... | Ireland, Leinster Dún Laoghaire-Rathdown | populated place population 8,821 | N 53° 18′ 5'' | W 6° 10′ 40'' |
| 300 | Birr Biorra,Bir,Birr,Parsonstown,biri,Бир,Бирр,ბირი | Ireland, Leinster County Offaly | populated place population 5,741 | N 53° 5′ 29'' | W 7° 54′ 48'' |
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