Revealing: In one of the river flooding scenes after the dam bursts, you can see a modern day vehicle (most likely a pickup truck) for a few seconds on a highway next to the river.

Revealing: Near the beginning of the film, when the team are cutting through the wire to steal an aircraft, look closely at the Lancaster bomber in the background. It is obviously a cardboard cutout.

Continuity: When Captain Drazak arrives at the camp carrying the bodies of the bandaged men, he passes in front of the child. The child makes fun with his right hand, but in the next shot, from behind, the child uses his left hand.

Factual error: The Force 10 finally manage to escape of the German ammunition depot by train. However, when the train leaves the tunnel and the men jump off the train the engine is a modern red and white electric locomotive. Only one problem: Electric trains did not exist in Yugoslavia until 10 years later.

Revealing: When Mallory, Miller and the others capture a German Schützenpanzer to infiltrate the train station for explosives, the wire they have strung across the road cuts off the head of a dummy.

Revealing: When Harrison Ford and Robert Shaw are preparing to blow up the dam in the tunnel, they insert their detonators into what is supposed to be plastic explosive, but looks rather more like Styrofoam painted brown.

Factual error: The tanks used by the Germans are Russian; it's the T34.