President Michael D Higgins will address a memorial this morning for the victims of the Dublin and Monaghan bombings in 1974.
The 50th anniversary commemoration marks the deaths of 34 people, including an unborn baby, in the single deadliest day of the Troubles conflict.
Taoiseach Simon Harris and Tánaiste Micheál Martin will attend the ceremony on Talbot street, where one of three explosions in Dublin happened.
A fourth blast in Monaghan town went off 90 minutes later.