Continuity mistake: In the final scene of the movie, when Riley is walking toward his car, he walks approx 30 feet from behind the car up to the car, notice that there are no other cars behind him. As soon as he starts the car he accidentally goes in reverse and we hear him crash into another car, yet there was no one behind him for at least 30 feet. We did not see or hear another car pull in behind him in that few seconds. There is no car parked behind him.Robert Sullinger
Continuity mistake: When Ben and Abigail are examining the Resolute desk at Buckingham Palace, Ben starts opening the drawers and discovers the code option numbers on the underside of the drawers for the first time. When he does this, in the shots of the underside of the drawer, Ben is pulling the drawers out almost all the way, but in the shots from above, he is barely pulling the drawers out at all.
Plot hole: In the beginning of the movie, year 1865, Thomas Gates is asked to decode the playfair cipher for the K.G.C. This is later found and decoded by Ben Gates, who discovers "Laboulaye Lady" to be the answer. In the scene when Ben and Riley go to France to see the Statue of Liberty, there is something written by Laboulaye, ending with the year 1876. As that writing was only added in 1876, Ben Gates couldn't have referenced it in 1865.
Plot hole: When the characters are trying to escape Cibola through the central drain, the drain is actually, as Ben and Patrick imply, really just a room which dead ends, and they have to open the door to keep it from filling up. If this were the case, the entire city of Cibola and the room above (where Ben first says that all the water goes out somewhere) would have been completely filled up with water over the centuries. But in the movie the water had apparently been draining through that central "drain."
Revealing mistake: When Nicolas Cage meets the president in the hangar and the president hands him a newspaper containing an article clearing Cage's great-great-grandfather's name, the text of the article in the center top of the newspaper in that scene contains the same body text as the article to the right that's titled "Family Saved."
Plot hole: The idea that Ben Gates had to run away despite the President's being okay with the kidnapping does not make sense. The President could simply pardon him if necessary. However, when he ran away, he would likely be committing other crimes (fleeing and eluding police, reckless driving, etc.) that would not be federal crimes and so would not be pardonable.
Factual error: When Ben and Riley are in a reading room in the Library of Congress, they have books about the architecture of buildings, as well as books about security and such. However, the particular reading room they are in contains books about Social Sciences, and to order books from a different area, it takes a really long time. They would have been in a different reading room that contained books about their subject.
Factual error: While the group was in the gold cave, Riley helps himself to one of the gold bricks, which is larger than a "standard" gold brick, and is roughly three inches thick, eight inches wide, and about twelve inches long. A brick of gold this size would weigh around 250 pounds, which would make it nearly impossible for Riley to carry around, even in a backpack. Even if it were ten carat gold in the brick, it would still weigh over 100 pounds.
Factual error: In April, any lake in South Dakota is freezing cold. And it goes without saying that you don't have to be in cold water very long for hypothermia to take effect; even a few minutes is enough. So why don't our heroes succumb to any kind of hypothermia when the gold chamber floods with icy lake water?
Factual error: When the group comes to Mount Rushmore, they arrive at a lake. There is no lake close to Mount Rushmore (look at Google Maps, the lake used is Sylvan Lake, which is a good 15 miles away from Mount Rushmore). Mount Rushmore is suppose to be a "cover up" for the final treasure and that would make the chamber underneath the faces itself. (01:27:05)Shamru
Factual error: When reviewing the picture having been caught driving through the traffic camera in London, the speed the car was travelling at is displayed in km/h. In the United Kingdom speed limits and fines are in miles.