It is 100 years since the final decision was made on exactly where the border would divide the island of Ireland.
On 3 December 1925 the Boundary Commission plan to adjust the border and take some places out of Northern Ireland, including Crossmaglen in south Armagh, was ditched at the last minute in a British-Irish deal.
Historian Cormac Moore says \"it gave of lot of certainty that had not been there before, particularly if you lived on the border and you were living in Fermanagh or Tyrone… you were not sure up until late 1925 that you were going to be in Northern Ireland or the Free State, and Cormac joined us on The Agenda this morning to talk to us some more about this.