Cork city’s boundaries are being extended from today, effectively adding 85,000 new residents to the city.
The first extension of the city boundary in over 50 years sees Ballincollig, Glanmire, Douglas, Frankfield, Grange, Blarney, Tower and Whites Cross become part of the city.
From today, Cork will be home to over 210,000 people and its projected that the city's population will continue to grow over the next 20 years reaching over 350,000 by 2040.
Over 400 public services will transfer to Cork city from the county as part of the expansion of the city.
Up to 550 km of roads, 990 social housing homes, nine cemeteries and three libraries will become part of the new city.
Also up to 134 staff have transferred to Cork City Council from Cork County Council and a further 70 new posts are also being filled.
Cork City Lord Mayor, Cllr Mick Finn, said: "As we welcome communities previously in County Cork to the city, we look forward to them bringing their expertise and experience with them.
"Tidy Towns organisations, community groups and services have transformed towns on the periphery of the city and enhanced the quality of life for residents. Joining that together with the fantastic community work undertaken by residents of the existing city will help inform the work of the newly elected Cork City Council".
City Council Chief Executive Ann Doherty said: "Cork is going through a period of unprecedented economic growth with up to half a billion euro of development underway or in planning in the city. The historic expansion of the city allows Cork City Council to plan for a city of sustainable urban growth and realise Cork's potential as a city of scale.
"We looking forward to working with communities in the new city in the months ahead.".