Gregory Peck was 44 in The Guns of Navarone when he played the character 'Capt. Keith Mallory'.
That was over 63 years ago in 1961.
In 2003 he died aged 87, starring in 94 films in his career, 57 of those after The Guns of Navarone was first released. If he were alive today he would be 108.
In The Guns of Navarone, I think Gregory Peck looks: