Irish Sea Cities and Towns Cities and Towns

| Rank_ | City_Town | County | Region_Province | Population | Country |
|---|---|---|---|---|---|
| 15 | Dundalk | County Louth | Leinster | 35085 | Republic of Ireland |
| 16 | Rhyl | Denbighshire | Clwyd | 35000 | Wales |
| 17 | Bray | County Wicklow | Leinster | 31901 | Republic of Ireland |
| 18 | Thornton-Cleveleys | Lancashire | North West | 31157 | England |
| 19 | Colwyn Bay | Conwy | Clwyd | 30265 | Wales |
| 20 | Carrickfergus | County Antrim | Ulster | 27201 | Northern Ireland |
| 21 | Fleetwood | Lancashire | North West | 26840 | England |
| 22 | Douglas | N/A | Isle of Man | 26218 | Isle of Man |
| 20 | Workington | Cumbria | North West | 25978 | England |
| 23 | Whitehaven | Cumbria | North West | 25500 | England |
| 24 | Dún Laoghaire | Dún Laoghaire–Rathdown | Leinster | 23857 | Republic of Ireland |
| 25 | Llandudno | Conwy | Clwyd | 20090 | Wales |
| 26 | Larne | County Antrim | Ulster | 18228 | Northern Ireland |