Continuity: When Cornelius meets the girl in the red dress and they dance and sing outdoors on the street, her dress is dragging on the pavement and the hem is clearly filthy. The next scene they arrive at the restaurant and her dress is clean and pressed.

Factual error: Hello Dolly is set in 1890. Barnaby makes several references to seeing "the stuffed whale at Barnum's museum" several times. But by 1890, Barnum's museums had burned down (three times, I think) he'd gone into politics, become a lecture speaker and finally had become partners with James Bailey to create Barnum and Bailey's Circus. (They even have a banner in the parade on 14th Street.) I doubt they still had the museum operating under his name.

Continuity: When Dolly first sits down at the table at the Harmonia Gardens, she picks up her napkin twice.

Factual error: In the original theatrical release print of this film, set in the 1890s, there is an overhead shot of a train travelling through the countryside from Yonkers to New York City. As the camera follows the train, an overturned 1950s-60s automobile in a ditch beside the track comes into view. The offending vehicle has been edited out of the video release.

Continuity: When Dolly is purchasing the ticket to Yonkers, she gives the money twice to the cashier.

Continuity: In the opening scene of the film, when the sepia toned picture of Old New York turns fluidly into a moving image, you can see a window air conditioner in the top left hand corner of the screen.