Relatives and families of those killed in the Claudy bombings 50 years ago will later gather in the quiet village of Co Londonderry to celebrate the anniversary.
A cross-community service with readings and hymns will take place 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 Kathryn Eakin, who had cleaned the windows of her family’s grocery store, Patrick Connolly, 15, and 16-year-old William Temple.
The murdered adults were Artie Hone, 38, Joseph McCluskey, 39, Elizabeth McElhinney, 59, James McClelland, 65, Rose McLaughlin, 52, and David Miller60.
The attack was blamed on the Provisional IRA, although the group never claimed it.
No one has ever been convicted of the attack.
Several of the next of kin took legal action against the Catholic Church after a 2010 police ombudsman report identified a Catholic priest, the late Father James Chesney, as a suspect.
The report said police, the state and the Catholic Church covered up his suspected role in the bombing.
Victims’ Group South East Fermanagh Foundation (SEFF) has supported the families over the past 12 months in developing a range of projects and events to mark the anniversary.
Director of services Kenny Donaldson said: “We have been in a relationship with the Claudy families for a number of years, but over the past 12 months we have worked with all nine bereaved families, the injured, the churches, schools and a range of others in developing a series of events to mark a milestone 50th birthday.”
He added: “The bombing of Claudy was an attack on the entire community of the area and it showed nine innocent deaths, young and older, male and female, Protestant and Roman Catholic – these neighbors died together and Claudy as a small village was changed forever.
“The bereaved have shared their life experiences of the past months with an appointed project facilitator, culminating in the production of a publication that will be launched on the day of the anniversary.
“The schools have also developed a digital project, where they work together in partnership and look at the past within Claudy, the present and what they wish for the future.
“A public service will also be held on Sundays at the Claudy Memorial and in the main parking lot, starting at 3:00 PM.”
SDLP East Derry MLA Cara Hunter has said the impact of the Claudy bombing continues to have a major impact on the area after 50 years.
She said: “My thoughts are with the families of the victims and everyone involved in the run-up to the 50th anniversary of the Claudy bombings.
“The events of that day have cast a dark shadow over this village that exists to this day.
“As a result of these bombings, multiple families and a community were torn apart and for many the pain is as real today as it was when this shameful act was carried out.”