Factual error: First time I ever saw a 600 mile NASCAR race where nobody had to make a tire change.
Continuity mistake: Throughout the movie, Alan Arkin is carrying in his breast pocket a Cross Chrome pen to write messages with on his pad. (He is a deaf mute.) But in the scene where he is on the porch with Sondra Locke and he is drawing a picture for her, he pulls that pen out of his pocket, yet when the scene cuts to a different angle showing him actually drawing on his pad, it is a thick, black felt tip pen. (01:25:00)
Factual error: When Premier Kamenev shows Kiril a map over the Chinese-Soviet border, it shows the Korean peninsula as a part of China.
Continuity mistake: When Gregor and Willie are attacked by the German convoy, they pick up two discarded StG 44s, but in th next scene they are firing AK-47s which had not yet been invented. After the battle, they are again carrying StG 44s.
Continuity mistake: When Matt and Freya are in the car chase, the driver's side of Matt's car is badly damaged. After escaping their pursuers, they drive off (in the same car) and return to Copenhagen. When Matt pulls into town, the side of the car is intact again.
Revealing mistake: When Buck and the gang ride away from the saloon in Dallas where JC made a few new 'friends', the footage is sped-up for a second just as soon as James Caan jumps on his horse. (00:05:50)