Trivia: At the very end of the film when Gregory Peck and David Niven are standing on the deck of the warship watching the explosions, you can see a very distinctive injury on Niven's upper lip. During the filming of the sequence where the commandos climb the cliffs he was slammed into the rock face by the water dumped on them to simulate the waves breaking over them. The resulting infection put him in hospital. He complains about the indifference of the film's producers in his book "The Moon's A Balloon."
Trivia: Michael Hordern plays Charlton Heston's father in the movie. In real-life, Hordern was only 12 years older than Heston.