Revealing mistake: In the final shot of the film the model makers neglected to include the antenna at the top of the Eiffel Tower, seen previously on the real tower in the establishing shot of Paris. (02:31:20 - 02:37:10)
Revealing mistake: The rock behind Tony Curtis while he is standing in his car to the left of him has a horizontal line across it where the two fake pieces fit together. (01:05:00)
Audio problem: In the beach scene near the beginning, Leslie Special comes to a screeching halt in front of Leslie's tent on a bed of sand. Can't burn rubber there.
Chosen answer: The cars and drivers were supposed to make the trip by ship from North America across the Bering Strait to a Russian port, where they would resume the race. As it happened, Leslie and Fate were stranded in a blizzard on the North American side before they reached the ship. The ice beneath their cars unexpectedly broke away and drifted across the Bering Strait, improbably arriving at the intended destination port in Russia. As they drift into port, we see Leslie's right-hand man, Hezekiah, waving at them from the Russian dock, which is only possible if Hezekiah made the journey by the very ship that Leslie and Fate missed.
Charles Austin Miller