The Yegg Foes in Gotham (2) - S2-E14
Continuity mistake: Just before Bruce Wayne tosses the grape to set it off, Egghead's miniature radar bomb moves to a different position on the floor all by itself. (00:04:00 - 00:05:20)
The Yegg Foes in Gotham (2) - S2-E14
Visible crew/equipment: During the final egg fight, the microphone shadow puts in an appearance on the wall behind the bad guys. (00:21:50)
The Yegg Foes in Gotham (2) - S2-E14
Visible crew/equipment: After Bruce defeats the radar egg using a grape it cuts to Commissioner Gordon at the raccoon pellet ceremony, and when the millionaires walk in, there are two chalk T-marks visible on the floor, beside Chief Screaming Chicken.
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