On June 6th 1944, over 156,000 soldiers stormed the beaches of Normandy or were dropped behind enemy lines 24 hours earlier.
The operation, code named Operation Overlord, was the beginning of liberation of Europe from Nazi Germany, oppression and the beginning of freedom.
Despite ferocious opposition by the Nazi defenders the Allies gained a foothold in Europe.
The cost in lives, is difficult to determine, but it is thought that at least 10,000 casualties were sustained by the Allies on the 6th June 1944.
That is the equivalent of 7 men being killed, wounded or missing in action every minute.
To mark the 74th Anniversary of D-Day a commemorative service is being held at Beacon Quay at 11am.