The President will lead a ceremony in Dublin today, to commemorate the 1916 Easter Rising.
O'Connell Street will remain closed to traffic as the Air Corps stage a fly-past, following a ceremony at the GPO at noon.
The Taoiseach, Micheal Martin, and Minister for Defence Simon Coveney will also attend.
Meanwhile, relatives of the 1916 signatories to the proclamation, are hoping to be granted an oral hearing by An Bord Pleanala, aimed at overturning planning permission granted by Dublin City Council for a new development on an historic site.
The Save Moore Street Campaign aims to prevent the demolition of the historically significant buildings associated with the Rising in Moore Street.
Founder of the campaign, Patrick Cooney, said they are still hopeful of a positive outcome.