Factual error: As Ben is clinging to the staircase while it is falling apart, there is a close-up of a nail being pulled out of the wood. This nail is round-headed, rather than square as it would have been over 200 years ago. It's also shiny instead of rusty, which indicates that it's galvanized. Galvanization as an industrial, metal-preservation process was not patented until 1837, and was not used in building materials until well into the late-1800s. Since the film states the staircase was made by "the Founding Fathers, " and there was no galvanization of iron nails in any industrialized nation in 1780s-1830's, this is a huge anachronism.
Factual error: When Dr. Chase receives the Washington campaign button from Ben Gates, she immediately picks it up with her bare fingers and rubs it with her thumb. An expert collector would *never* handle metal objects with their bare hands like this, as the acid on the fingers will corrode the metal. Cleaning the coin afterwards is also not an option, as this presents an even higher damage risk. See http://www.stujoe.com/content/view/30/34/ for more details.
Factual error: During the heist preparation scene, Riley enters the National Archives Metro station to record surveillance camera footage. Surveillance camera feeds for the National Archives would never be accessible within a Metro station due to both security concerns and the fact that the feeds are not needed outside of the National Archives building.
FBI: Here are your options. Door number one you go to prison for a very long time, door number two you help us get back the declaration from Ian, and you'll still go to prison for a very long time, but you'll feel good inside.
Ben Gates: Is there a door that doesn't lead to prision?
FBI: Someone's gotta go to prison, Ben.
Riley Poole: Asuming Ben's theory is correct and my tracking model's accurate, we should be getting very close. But don't go by me, I broke a shoelace this morning. It's a bad omen.
Ian How: Should we turn around and go home?
Ben Gates: Or we could just pull over and throw him out here.
Riley Poole: Ha, ha, ha, okay.
Ben Gates: Well Riley, you're not missing that small, windowless cubicle we found you in are you?
Riley Poole: No, no. Absolutely not.
Question: Ben explains the code on the Declaration reading 'Heere to the Wall' refers to the corner of Broadway and Wall St. But inside the church he reads 'Beneath Parkington Lane' and assumes that must mean beneath the church. But why is there no explanation for what Parkington Lane is and why wouldn't Ben think it's just another clue?