The Taoiseach, Mr Ahern, will walk down a remote country lane to the Widow McCormack's house tomorrow to honour the leaders of the Young Ireland movement who developed the ideals of the United Irishmen and attempted a rebellion in 1848.
He is expected to announce the purchase by the State of "The Widow McCormack's House", where the brief rebellion of the Young Ireland movement collapsed abruptly, although the ideas it stood for became a major influence on the course of Irish history.
Mr Ahern's visit to the two-storey slated building outside the village of The Commons, in the Slieveardagh region of east Tipperary, coincides with wide-ranging local celebrations organised to commemorate the 150th anniversary of the rising.
"The Warhouse", as the building is known locally, was the site of a minor battle when a couple of hundred largely unarmed local followers of the Young Ireland leader, William Smith O'Brien, besieged a party of armed police in the house of the young Widow McCormack and her children.
The siege collapsed when O'Brien, a Protestant landlord and aristocrat, refused to permit setting fire to the house, and news of the approach of police and troop reinforcements reached the rebels.
The Young Ireland leaders realised the futility of their ill-prepared attempt to raise a rebellion among a famine-stricken and weaponless people, and O'Brien gave the order to disperse.
The Times of London derisively called the rising, "The Battle of the Widow McCormack's Cabbage Patch".
The Young Ireland leaders fled or were transported into exile, and went on to establish influential positions in Australia and the US, from where they continued to focus on Ireland's troubles.
The ambitious "1848 Festival" taking place this week includes a massive historical pageant, traditional music and historical lectures. It is organised by Slieveardagh Rural Development (SRD), whose members believe that a lack of understanding of this immensely important movement in the country's history is still prevalent in Ireland.
It is hoped that the State's purchase of the famous "Warhouse" will help towards a reappraisal of the non-sectarian political and cultural movement that bloomed briefly in the 1840s.
The penal colonies of Tasmania were the enforced "home" of many of the Young Irelanders in the aftermath of the rising's failure, and several hundred people from Tasmania are attending the festival in Slieveardagh.
The Taoiseach will arrive by helicopter at the once-thriving coal-mining village of Ballingarry, where he will take part in a ceremony at the National Flag Monument, claimed locally to be the place where the Tricolour, introduced by Thomas Francis Meagher, was first raised publicly.
Many direct descendants of the Young Irelanders will be present when Mr Ahern unveils a plaque at the Widow McCormack's House and pays tribute to Thomas Davis, founder of the Nation newspaper; James Fintan Lalor, campaigner on land reform; John Mitchel; John Blake Dillon; and Charles Gavan Duffy.
A plaque to William Smith O'Brien, leader of the 1848 Rising, will be unveiled today at his birthplace, Dromoland Castle, Co Clare, at 5.30 p.m. The rising ended 150 years ago today.