The Countess of Antrim laid the foundation stone of Knockagh Monument on October 7, 1922. And Mid and East Antrim Borough Council lit up the imposing landmark on Friday to mark this significant milestone.
A wreath laying ceremony also took place attended by representatives of the County Antrim councils who have taken care of the monument.
Meanwhile, Dr Paul Harron, chief executive of the Ulster Architectural Heritage Society, was guest speaker at a talk held in Carrickfergus Museum and Civic Centre on the architect who designed the monument, Henry Seaver.
Among those helping to mark the centenary was the Earl of Antrim, who officially launched a travelling exhibition about the memorial. Running until October 13 at the Antrim Street museum, it includes photographs of modern commemorations of the Battle of the Somme as well as wartime artefacts.
1. Milestone marked
Marking the centenary of the imposing landmark. Photo: Contributed
2. Poignant moment
A poignant moment from Friday's service at Knockagh Photo: Contributed
3. First citizen
The Mayor of Mid and East Antrim, Ald Noel Williams, lays a wreath on behalf of the citizens of the borough. Photo: contributed
4. Centenary service
Participating in the centenary service at Knockagh Monument Photo: Contributed