Goofs:
Crew or equipment visible: When the captured German Alpine Post Bus races throughout the airfield, Schaffer and Mary shoot several small jeeps which flip over. As they do, the rope that flipped them can be seen being pulled off screen. (more)

Trivia:
In the scenes where Richard Burton and Clint Eastwood climb the step fortress walls, Burton moves with ease, while Eastwood is clearly working hard physically. This was due to the fact that Burton, who was a hard-drinker and out-of-shape by that point, chose to ride a crane (made invisible by special effects) up the wall, whereas the young, healthy Eastwood was actually climbing the wall. (more)

Filming Locations:
Aigen im Ennstal, Steiermark, Austria (more)

Quotes:
Major John Smith: Lieutenant, in the next 15 minutes we have to create enough confusion to get out of here alive.
Lt. Morris Schaffer: Major, right now you got me about as confused as I ever hope to be.
(more)

Awards:
2 nominations (more)