This Christmas will mark the 50th anniversary of a Belfast jail-break where two men breached security at the prison known as "Europe's Alcatraz".
Donal Donnelly and John Kelly, both jailed for IRA membership during its short-lived 1950s campaign, reached the perimeter of the top security Crumlin Road Gaol on the night of December 26, 1960.
But as they struggled against a snow storm, their home-made rope of electrical flex and bed sheets snapped in half, sending them tumbling over opposite sides of the 30-foot wall.
Donnelly fell outside the jail and despite suffering a broken heel, broken hand and crushed spinal cartilage, his memoir, Prisoner 1082, recalled how he escaped despite a massive manhunt.
Kelly landed on the wrong side of the wall. In extensive interviews, taped before his death in 2007 but never made public, he recorded his jail experiences and how he later rose to prominence.
Following the explosion of violence in Northern Ireland in 1969, his efforts to secure guns from the Irish Government for nationalist communities saw him in the dock alongside future Taoiseach Charles Haughey in Dublin's infamous Arms Trial.
At around the same time, he was one of the founding members of the Provisional IRA. He also played a role in the peace process decades later.
Recalling the Crumlin Road break-out, he said: "It was a failed escape attempt for me but I was happy that one of us got away. It was important to have breached security at a time when the Crum was seen as escape-proof. I didn't get away but it was still a success."
Donnelly eventually went into hiding in Cork and ended up building a new life and a successful business career in the Republic. John Kelly was placed in solitary confinement, sentenced to a further six months behind bars and stripped of of prison privileges.
The Crumlin Road Gaol closed in 1996 and is now being transformed into a grisly tourist attraction.