Continuity mistake: In the last scene, inside the coach, Marie Antoinette looks out the window at the palace garden. Louis asks if she's admiring her new lemon tree avenue; she answers she's only saying goodbye. If you look at the view of the window when Louis asks the question, you can see half of the fountain and the lemon tree avenue quite close. Next frame, when Marie answers, you can see almost the whole fountain and the lemon tree avenue quite far from where the coach is.
Continuity mistake: At the beginning, when Marie Antoinette gets into the carriage she is on the left side, but when the camera focuses on her again she is sitting on the right side. Also, she is wearing a blue dress when she arrives at the tent, but when she gets out of the carriage her dress is white.