A decision by Dublin City Council to grant planning permission for an office block and technology park opposite Kilmainham Gaol has been overturned by An Bord Pleanála.
The controversial development, which was planned by Charmside Ltd, a subsidiary of Treasury Holdings, was opposed by local residents who had the backing of An Taisce, the national trust.
The development would have comprised 55,902 square metres of accommodation in three blocks up to six storeys high on the site of the former Rowntree-Mackintosh factory on Inchicore Road.
An Bord Pleanála, in turning down planning permission for the proposed development, said the site was close to several protected structures including Kilmainham Gaol, which is now a museum, national monument and tourist attraction.
The board ruled that one of the blocks would "materially and adversely affect the setting of Kilmainham Gaol by reason of its close proximity to the gaol, its monolithic nature and its height" and would therefore be contrary to the proper planning and development of the area.
It also found that two residential terraces adjoining the side and rear of the site would be overlooked by the development, resulting in "significant loss of sunlight and visual obtrusion" for them.
In addition, the appeals board said one of the proposed buildings would "encroach excessively" on the space at the junction of Inchicore Road and the South Circular Road and "would fail to respect the setting of the Richmond Guard Tower and Kilmainham Courthouse".
It added: "The proposed development would, therefore, diminish the current and potential amenity value of this space and be contrary to the proper planning and development of the area."
Mr John Callery, chairman of the Friends of Kilmainham, said the decision issued yesterday was a big victory for the local community.
"It's a very historic 12th of July in Kilmainham," he said.
The appeal went to an oral hearing last February where the developers argued that the proposal was appropriate for the location as the site was zoned for enterprise and employment.
Mr Tom Phillips, representing developers, told the hearing the development was also in sympathy with its surroundings and would feature large amounts of natural stone, possibly granite and limestone, so that it was in keeping with the Gaol and other buildings.