Factual error: If you take the train from Paris to Cannes you won't pass the Eiffel tower.
Factual error: Kate and Charlie live in Toronto. When we first see them in their car, at the beginning of the movie, it has no license plate in the front. In Ontario, cars are required by law to have a plate in the front as well as in the back. While some jurisdictions may be lax in applying their two-plates law, Ontario isn't.