Revealing mistake: When Napoleon Solo arrives at the train station, both the name of the newspaper the man in black is holding, and the name on the station sign are backwards. Additionally, as he arrives by train the man in black is on the left side of the shot. After exiting the train, the man in black appears from the right side of the shot.
Continuity mistake: As Napoleon Solo arrives by train, he passes two donkey drawn carts and approaches a woman whose sweater collar is overlapped from right to left. In the next shot, showing Solo exit the train, the donkey carts are now to the right and the woman's collar is now overlapped left to right.