Irlanda
Países del mundo
O
- (Limerick City and County Council) Odell Ville
- (Clare) Oughterard
- (Kilkenny) Oldtown
- (Kilkenny) Oldtown
- (County Tipperary) Outeragh
- (Limerick City and County Council) Oldtown
- (Wicklow) Oghil
- (Wexford) Old Bawn
- (Wexford) Oulartwick
- (Wexford) Oulartleigh
- (Kilkenny) Ossoryhill
- (Wexford) Oldcourt
- (Kilkenny) Oldgrange
- (Kilkenny) Oldcourt
- (County Tipperary) Oaklands
- (County Tipperary) Oldgrange
- (Kerry) Oghermong
- (County Galway) Oileán na Tuí
- (County Galway) Oileán Dá Bhranóg
- (Sligo) Oyster Island
- (Roscommon) O’Reilly’s Island
- (County Galway) Oghly Island
- (Kerry) Ormond’s Island
- (County Cork) Owen’s Island
- (County Galway) Omey Island
- (County Cork) Orthon Island
- (County Donegal) Owey Island