Continuity mistake: When Kong is about to be captured and people jump on the boat, their positions differ between the front angles and the ones shot from behind.
Continuity mistake: After Kong kills the dinosaur, when he pounds his chest, watch a branch on the left. It's sometimes up or suddenly down. Most surely due to the animators moving it inadvertently while operating the models.
Continuity mistake: When Kong fights against the dinosaur, Ann's tree starts to fall, and she cries while waving her right arm and holds onto it with her left. The shot changes, and now it's the opposite way: she is holding onto it with her right arm and waving her left hand.
Revealing mistake: When Kong strips Ann, it is a composite of two images: footage of a huge mechanical arm holding her and a puppet Kong in a miniature set. The arm footage is noticeable because the background wobbles, and the pasted area stands out from the miniature set behind.
Continuity mistake: In New York, Kong fetches a woman in her sleep. In the close-ups she's wearing white pyjamas, but the mannequin she's replaced for when she falls has short hair and dark clothes.
Continuity mistake: While Kong kills the pterodactyl Jack arrives to save Ann. Shot changes and he's back in the cave making his entrance again.
Continuity mistake: The two villagers that are stomped by Kong's foot are bald but grow an afro in the close-ups.
Continuity mistake: Kong keeps changing styles throughout the movie at least 4 times: In the close-ups of its head it either has a round face with dirty teeth, fangs and small nostrils or white teeth with no fangs; as opposed to the full body models where it swaps between a cone-head forehead with small nostrils, and a rounder one with larger nostrils, both models with pearly white teeth.
Continuity mistake: The right cuff of Kong's shackles disappears from his wrist when he destroys the train, only to reappear later on.
Continuity mistake: When Ann watches Kong fight the dinosaur, her position is inconsistent between the wide shots and the close-ups.
Continuity mistake: During the fight between Kong and the dinosaur, the shape of the tree Ann is on differs between shots.
Continuity mistake: When Kong brings Ann's bed towards him, the footboard changes between the wide outside shots and the inside shots.
Continuity mistake: The planes that attack Kong have two parallel wings, the lower wing being shorter. In the close-up of the planes next to Kong both wings are the same size.
Revealing mistake: When Kong is about to attack the train, the building on the right (a superimposed projection) wobbles like jelly for unknown reasons. It's not because of Kong's footsteps, for it never happens in any previous scenes.
Continuity mistake: When Kong lifts Ann from the bed she is wearing a short dress. In the close-up the dress goes way down to her ankles.
Continuity mistake: Kong breaks the window and Ann starts to shout and extends her right leg. A shot later it's bent downwards.
Continuity mistake: Kong breaks the window and takes Ann from bed. In the wide shot (where she's replaced by a stop-motion doll) she faints backwards. In the immediate close-up she is conscious and upright.
Continuity mistake: After Kong escapes from the theater, a car crashes against a wall with no glass on the windshield. In the next shot, broken glass appears.
Revealing mistake: At the Empire State, Kong extends his arm to grab the woman. Problem is, instead of catching her she magically flies up the air to his hand.
Revealing mistake: At the Empire State, the woman is an obvious square-shaped footage of film pasted on top of the footage of Kong. After the plane attacks Kong and his right arm goes limb it goes behind the pasted footage.
Answer: It's never shown or explained, and the film uses a broad "suspension of disbelief" premise. The audience just accepts the characters were able to somehow transport a huge ape to New York City.
raywest ★