The survivors and families of those killed in the Claudie attacks 50 years ago will gather later in the quiet village of Londonderry to mark the anniversary.
an intercommunal service with readings and hymns will be held at the memorial in the village.
Nine people, Catholics and Protestants, were killed and 30 injured when three car bombs exploded in the village on July 31, 1972.
Among the victims were nine-year-old Catherine Eakin, who washed the windows of her family’s grocery store, Patrick Connolly, 15, and 16-year-old William Temple.
The adults killed were Artie Hawn, 38, Joseph McCluskey, 39, Elizabeth McElhinney, 59, James McClelland, 65, Rose McLaughlin, 52, and David Miller, 60.
The attack was blamed on the Provisional IRA, although the group never claimed it.
No one has ever been convicted of assault.
Several families of the victims are continuing legal action against the Catholic Church after a police ombudsman’s report in 2010 revealed that the suspect was a Catholic priest, the late Father James Chesney.
The report said police, the state and the Catholic Church covered up his alleged role in the bombing.
The South East Fermanagh Foundation (SEFF), a group of survivors, has supported families over the past 12 months in developing a range of projects and activities to mark the anniversary.
Director of Services Kenny Donaldson said: “We have had relationships with the Cloudy families for a number of years, but over the past 12 months we have worked with all nine families of the dead, injured, churches, schools and more. in the development of a series of events dedicated to the significant 50th anniversary.
He added: “The explosions in Claudy were an attack on the entire population of the area, and it was proved by the death of nine innocent people, young and old, men and women, Protestants and Catholics – these neighbors died together, and Clody as a small village was forever changed.
“The families of the victims shared their life experiences in recent months with the project’s designated curator, culminating in the publication of a publication to be released on the anniversary day.
“The schools have also developed a digital project, working together in partnership to explore Cloudy’s past, present and what they desire for the future.
“There will be a community service at the Claudie Memorial and the main car park on Sunday starting at 3:00 pm.”
SDLP East Derry MLA Kara Hunter said the Cloudy explosion still has a strong impact on the area 50 years later.
She said: “My thoughts are with the families of the victims and all those affected as we approach the 50th anniversary of the Claudie bombing.
“The events of that day cast a dark shadow over this village, which remains to this day.
“As a result of this bombing, several families and communities were torn apart, and for many, the pain is still as real as it was when this shameful act was committed.”