In May 1919, a Memorial Committee discussed a Wayside Cross to be erected in memory of those who served in the First World War and in May 1920 the Committee decided on an Iona Cross of Canadian grey granite. The cross was a gift from Trinity College School Ladies' Guild and dedicated on June 11, 1922.
After a service in the chapel, the choir proceeded to the Cross followed by students in two long lines. The boys lined on each side of the Cross in a broad V facing north and to the south stood the choir in four ranks. Sixteen Old Boys, cadets at the Royal Military College, formed a guard of honour in a hollow square on the north side. To the east stood the Headmaster, Dr. Bethune and First World War Veteran Major-General Sir A.C. MacDonell, who unveiled the cross. Mrs. Lawrence Baldwin, on behalf of the Ladies' Guild, made a formal presentation of the Cross. The act of dedication was performed by Dr. Bethune.