Smack in the Middle (2) - S1-E2
Factual error: The mammoth is filled, according to the Prime Minister of the Republic of Moldavia, with "used postage stamps from ancient kingdom of Moldavia." Postage stamps are a 19th century invention, not something an 'ancient kingdom' would have used. (00:17:20)
Smack in the Middle (2) - S1-E2
Factual error: Nitrous oxide is not flammable. Not to mention, if it were, Riddler would have risked blowing everything up when he shot the gun in the room saturated with it just to give his henchmen the signal.
Answer: There wasn't one singular city used. It was shot in and around various locations in California, plus on a lot of sets and backlots. Ex. Some scenes were shot in LA, some in Pasadena, some in Santa Barbara, etc.
TedStixon