Continuity: When the two meet on the train and engage in conversation, the views outside the train don't match when we cut back and forth between Jesse and Celine.
Audio/visual unsynchronized: You can hear people screaming in the roller coaster, but there is no one sitting in it.
Errors made by characters (possibly deliberate errors by the filmmakers): In Vienna, Jesse talks about his obsessive relationship with "Miss July, 1978" of Playboy magazine, then asks Celine if she knows Crystal. Playboy's Miss July 1978 was actually Karen Morton, cousin of 1970s model Elaine Morton.
Errors made by characters (possibly deliberate errors by the filmmakers): While telling the story about the death of his grandmother, Jesse first says he was attending the funeral of his great-grandmother. From then on he always refers to his grandmother.
Continuity: Jesse has been traveling through Europe by rail for 2-3 weeks and yet when the two men on the bridge tell him their play starts at "21:30" he is lost at what that means.