The proposed plans to turn College Green into a pedestrianised civic plaza have been refused by An Bord Pleanala.
The €10million development was first proposed by the Dublin City Council in 2016 with a decision initially due for the end of last year, however it has been delayed multiple times since.
An Bord Pleanala said the proposals 'would produce a quality public realm that would significantly enhance the amenity and attractiveness of this city centre location'.
However, the Board also outlined 4 reasons for rejecting the proposals, including the impact on pedestrians, bus-users and taxi drivers.
In the boards decision, it states that the pedestrianised area would 'likely significantly negative impacts for bus transport, in the light of the scale of re-routing of buses proposed'
The authority also said that it had "unacceptable" safety concerns regarding cyclists, pedestrians, buses and emergency vehicles.
