Raiders of the Lost Ark (1981) - 96 mistakes
Directed by Steven Spielberg, starring Alfred Molina, Denholm Elliott, Harrison Ford, John Rhys-Davies, Karen Allen, Paul Freeman
Factual error: The German submarine that Indy stows away on has the number 26 on its side. The U-26 was a Type IA U-boat (it came into service in 1936 and was sunk in 1940), but the sub in the movie seems to be a Type VIIB or VIIC. It's true that the two types looked fairly similar, but they were different classes of U-boat.
Continuity: As Indiana writes "Neolithic" on the blackboard in his classroom at the beginning of the movie, he stops and checks to see if he's spelling it right, then finishes writing it. Later shots of the board reveal the same word on the board, only either the handwriting is different or the actual structure of the word has changed.
Continuity: Near the middle of Marion's introductory scene in her bar in Nepal - after Indy has left the bar - she sits down at a table and pulls the medallion out from the front of her shirt where it was hidden, hanging on a chain around her neck. The next shot shows her laying it on the table, chain and all, without lifting the chain over her head.
Continuity: The stone block Indy pushes out to create an opening which allows him and Marion to escape the Well Of Souls apparently rolls down the hill outside. We see it, in a following scene, laying about 15 feet away from the Well. But when Indy is fighting the big German guard near the airplane, one scene clearly shows the Well in the background and the dislodged stone is now laying on the hill only a few feet from the opening.
Continuity: Before the shoot-out in Marion's bar, after the creepy Nazi asks her for the amulet, she's sitting alone at the table. She pulls the amulet out of her shirt, the chain still around her neck, and stares at it in the candlelight. The next moment the chain is not around her neck and she hangs the necklace onto the table centrepiece.
Continuity: In the chase through Cairo streets - Indy rounds the corner of the plaza in which the truck (supposedly holding Marion in a basket is kept) - as Indy comes around the corner, a baddie shoots at him with a machine gun - watch this closely, the gun moves in the opposite direction as the bullets on the ground.
Continuity: During the scene where Indy and Marcus are with the Army intelligence agents, watch the agent who is wearing the light blue suit - at the moment when Marcus refers to a secret chamber, the agent in the blue suit has his right hand resting on top the chair that he is sitting on, but in the next shot when he replies "secret chamber" his right hand is now on his face.