All traffic, including buses and taxis, will be banned from College Green this Sunday.
It's part of a trial by Dublin City Council to see how the plaza could be put to use without vehicles.
A plan to permanently pedestrianise the area was shot down by planning authorities last year.
An Bord Pleanala argued the move would have a “significant and negative” impact on bus passengers, and taxis.
It also said it had "unacceptable" safety concerns for cyclists, pedestrians, buses and emergency vehicles.
Following the rejection, Dublin Chamber called for a trial to see how pedestrianising the plaza might work.
The first of those trials takes place this Sunday.
All traffic will be banned from 7am-7pm, while buses won't be allowed to travel East-West to and from Dame Street.
The trial will continue for three Sundays in a row, on July 21st and 28th, and August 4th.
#DBSvcUpdate Diversions to facilitate @DubCityCouncil trial closure of College Green on Sunday 21 July 2019 https://t.co/QDp9siHSN2 pic.twitter.com/Vu3b9GFoeO
— Dublin Bus (@dublinbusnews) July 18, 2019
Bus stops outside Ulster Bank, Starbucks and the old Central Bank will be closed.
North-South bus routes are not affected, meaning bus services will still pass in front of Trinity College.
The Luas will also still pass College Green, stopping at both Trinity and Westmoreland.
Brendan O'Brien, Head of Technical Services for Traffic from Dublin City Council, said it will be an "opportunity to experience the space without the through traffic being there".
He told 98FM's On The Move podcast that there will be a number of "low key" events organised for each Sunday.
They will be aimed at passers-by and families, with entertainers, sketching and science and technology themes spread out over the three weekends.
View some 3D Pavement Illusions and take some pictures to amaze friends and family. It’s all at Drawing in the City from 12 to 4 this Sunday July 21st as part of Summer Sundays on College Green.
Details at https://t.co/Gu0CTcXVoV pic.twitter.com/lBYEQoqmMJ— Events DCC (@events_DCC) July 17, 2019
While College Green has been closed for events before like the visit of Barack Obama and the New Year's Eve Festivals, this is the first time it will be closed to traffic without there being an actual need.
Dublin City Council is describing the trial closures as "Summer Sundays".
Cars driving from Dame Street will be allowed to turn right on George's Street to access the Grafton Street quarter and its car-parks.
Cyclists will be allowed to pass through College Green during the closures.
