A weekend of commemorations marking the centenary of the 1916 Easter Rising will start with a series of wreath laying ceremonies today.
Sabina Higgins, President Michael D Higgins's wife, will remember Countess Constance Markievicz at Glasnevin Cemetery while the President will lay a wreath at the Garden of Remembrance in honour of those who fought and died for Ireland's freedom.
Later, President Higgins is expected to meet the families of those killed during a special event in Dublin's RDS where he will speak about the debt of gratitude owed to the rebels immortalised in the history books as well as the "unsung heroes" who took to the streets one hundred years ago.
The President is expected to focus on the "human essence" of the rebellion reflecting on combatants' differing motivations as well as their influence in post-independence Ireland.
The Rising which began on Easter Monday, April 24, 1916 was a seminal moment in Irish history, sowing the seeds for a war of independence that led to partition of the country and the creation of the Republic of Ireland and Northern Ireland.
Some 1,350 people were killed or injured during the six day insurrection while 3,430 men and 79 women were also arrested by the British.
Fifteen of the rebel leaders including Patrick Pearse and James Connolly were executed by firing squad at Kilmainham Gaol in Dublin.
The biggest event of the weekend is due to take place on Easter Sunday when more than a quarter of a million people will line the streets for a massive parade through Dublin city centre.
Almost 4,000 members of the Defence Forces, emergency services and army veterans will weave their way along the 4.5 km route from St Stephen's Green to O'Connell Street and past the General Post Office on to Capel Street.
The unprecedented spectacle, which will begin at 10am with the reading of the Proclamation is being billed as the largest public celebration in the history of the state.
Wreaths will also be laid in Glasnevin at the Sigerson Monument, which honours the dead of 1916, and at the graves of Edward Hollywood, a silk weaver from the Liberties in Dublin who put together the Irish Tricolour in 1848, and the grave of Peadar Kearney, who wrote the lyrics to Amhran na bhFiann.
President Higgins will be in the Stone Breakers' Yard in Kilmainham to lay a wreath on the site where the 1916 leaders were executed.
Further commemorations are planned for Easter Monday at each of the seven key battlefield sites in Dublin.
Cultural events are also being held in more than 200 venues across the city including 500 free talks, exhibitions, debates, film, performances and dramatisations, with six outdoor stages and activities for children and families.
Outside of Dublin simultaneous wreath laying ceremonies will take place in Athenry, Cork, Enniscorthy and Ashbourne.