The Puzzles Are Coming (1) - S2-E31
Continuity mistake: In the Batcave, Batman is holding Puzzler's pink balloon while he and Robin deduce its clues. The shot cuts to a wider angle when they turn to race to the Batmobile, and the balloon disappears. (00:12:50)
The Puzzles Are Coming (1) - S2-E31
Revealing mistake: While The Puzzler and his baddies are at Artemus Knab's penthouse, across the street from Commissioner Gordon's office, when Puzzler decides he will launch the plane himself, the wire attached to the top of the plane is visible. (00:01:15)
The Puzzles Are Coming (1) - S2-E31
Revealing mistake: At the old balloon factory, when Puzzler throws the model airplane with a poison tip at Batman, on his upper arm we can see the protruding outline of the rectangular base to which the small airplane is attached. (00:22:00)
The Puzzles Are Coming (1) - S2-E31
Visible crew/equipment: At the Knab Aircraft hangar Puzzler arrives in the truck just as Knab is leaving, and when Puzzler walks to the back of the truck the reflection of the boom mic is visible on the right back door windows. (00:14:45)
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