Factual error: Proteus refills its air supply in the lungs. The lungs are filled with normal sized oxygen molecules. How are they supposed to breathe them? (In the book, they had a miniaturizer on the sub, but there is nothing in the movie to explain this.)
Factual error: John Wayne and James Caan are in the gunsmiths shop, and behind the gunsmith on the shelf are some products, one of these products is Bugler tobacco. Bugler tobacco was introduced in the United States in 1932. (01:00:00 - 01:02:00)
Factual error: Adam, who was not born of a woman and who would have no need for an umbilical cord, has a navel. (00:09:45)
Factual error: In the scene near the end of the film where Victor Buono is sitting in his chamber addressing his two captives, he opens a can labeled egg foo young with a can opener. He pours the liquid contents into a bowl. Egg foo young is an omelet and could not have passed through the small holes made with a can opener.
Factual error: The British carry WW-I, No 1 Lee-Enfields, and the Germans carry WW-II era British No. 4 Lee-Enfields.
Factual error: At the end, during the master wide shot of Diana and Shandor (C19 characters) standing over the castle moat, there is a modern aeroplane's vapour trail high above their heads.
Factual error: In the scene where Lee Marvin states that Burt Lancaster loves explosions, Burt Lancaster makes a remark about the big bang theory. He says: the whole universe started with a big explosion. The film is set in 1917 which is 10 years before Georges Lemaître launched the big bang theory.
Factual error: Racer Dave Owens goes down to an unspecified Southern state to race and becomes a moonshine runner. However, the Dodge he drives in his illicit activities possesses California plates, as does the Plymouth driven by the IRS agents.
Factual error: Cary Grant arrives at his Tokyo hotel two days early, and no rooms are available. He goes to his embassy, which, according to the sign on the gate is the "British Embassy". In reality, the sign would say, "Embassy of the United Kingdom of Great Britain and Northern Ireland".
Factual error: When Tuco is in the gunshop messing around with the guns, one gun has the cylinder and barrel moving back and forth by manipulating the trigger guard-lever. This is a Belgian Galand & Somerville revolver, a gun that did not exist until 1868. This film takes place during the US Civil War, which ended in 1865.
Factual error: When Riddler's rocket hits the Batcopter, the villains are watching from the periscope as Batman and Robin are crashing. However, the image they see is a straight-on shot, as if the lens were right in front of the copter. No pre-atomic periscope can reach that far up.
Factual error: When Mother Superior announces those girls who wish to stay and join the convent, she states they will join the Novitiate. Actually, not correct. Their 1st step is called Aspirancy / Pre-Candidacy Then Postulancy / Candidacy THEN they are a Novice, for a few years, before taking Final Vows to be a Full Nun.
Factual error: Alva and Owen go see the movie "One Way Passage", released in October 1932. The movie takes places in August, the year is not stated explicitly, but there's a wall calendar in the dining room at the boarding house (you can see it when Legate leaves, calling himself a fink) for 1934, and at the same time the date shown in the office (when Redford sits at the desk to decide who will get pink slips) is August 14, Friday, which would set the movie in 1931.
Factual error: Although set in 1860, virtually all the costumes/clothing in the film are far more typical of the later Victorian period. For example, the police are wearing cork helmets, tunics, and Duty Armlets with upright stripes. These items were not introduced into the Metropolitan Police until 1863, 1864, and 1886 respectively (and this would have been delayed further in a small backwater Cornish town). In 1860, they would be wearing top hats, swallow-tail coats, and Duty Armlets with horizontal stripes.
Factual error: The onlookers are eating pears in spring. Wrong time of the year for ripe pears.
Factual error: The uniforms worn by the engineering force are from the wrong era. Prior to 1941 the left arm rates had the head of the eagle pointing to the wearer's rear. Steve McQueen and the rest of the Engineering force rate eagle head is pointing forward, which is from WW2.
Factual error: The Dalek mine is set in Bedfordshire. We see the encampment with high mountains beyond. Bedfordshire is a county of low rolling hills, with virtually no rock.