Other mistake: After King Tut's men deliver the statue, it's referred to as a Sphinx. Even Batman says, "Rather good imitation of the 4th Dynasty's Sphinx at Giza." Problem is, the Great Sphinx of Giza is a reclining lion with a human head. The statue in Gotham's park is a ram's head atop a seated human body, resembling Egyptian God Khnum, and looks nothing like the Egyptian Sphinx. Bruce Wayne is a member of Gotham City Museum's Board of Trustees, which recently opened the new exhibit of Egyptian antiquities. (00:10:35)
Continuity mistake: While Bruce Wayne is lying on a gurney at the back of the ambulance, in the wide shot of Tut's henchmen driving along on the street, there's a rearview mirror on the windshield and a single beacon light on the roof, but in the closeups the rearview mirror is gone and there are two beacon lights on the roof. (00:21:30)
Factual error: Though he's a bastion of knowledge and a member of the museum board, Bruce Wayne completely mangles Egyptian history - twice. He says that King Tut ruled in the 14th Dynasty, and that the museum's mummy was a 14th Dynasty king who ruled in 1500 BC. Wrong on both counts. Tut reigned from 1336-1349 BC. The 14th Dynasty ran from 1773-1650 BC. Wayne would have known that - and so would his well-educated colleagues, none of whom points out the error. (00:13:00 - 00:15:00)
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