Minerva, Mayhem and Millionaires - S3-E26
Visible crew/equipment: At the start, in the two consecutive scenes with millionaires William Dozier and then Howie Horwitz, while they're being treated to Minerva's renowned scalp massage, the chalk T-mark is visible on the floor at the lower left side of the screen, and in the Horwitz scene Minerva's small mark is also visible on the floor behind the spa chair. (00:00:45)
Minerva, Mayhem and Millionaires - S3-E26
Visible crew/equipment: Minerva tells Freddie that if she'll get the diamonds from the Wayne Foundation vault, he can fence them. When it cuts to Commissioner Gordon, Batgirl, and Chief O'Hara pacing the floor, three small white tape marks are visible on the rug in front of the coffee table, where each of them stop and turn on their marks. (00:05:35)
The Entrancing Dr. Cassandra - S3-E25
Visible crew/equipment: After Alfred has placed the two-dimensional Terrific Trio into the Three-Dimensional Bat-Restorer, when they all walk out of the chamber, two chalk T-marks are visible on the floor. First we see Batgirl's T-mark and then Robin's. (00:16:50)
Nora Clavicle and the Ladies' Crime Club - S3-E19
Visible crew/equipment: When Batman and Robin are seated in the Batmobile with Batgirl standing alongside, while they listen to the ridiculous police dispatcher, the reflection of the moving boom mic is visible on the front windshield's chrome trim. (00:10:00)
Louie's Lethal Lilac Time - S3-E18
Visible crew/equipment: Commissioner Gordon and Chief O'Hara think Batgirl has joined Batman and Robin inside Louie's hideout, so they decide to stay put where they are. In the next shot, when two of Louie's goons report that the Batmobile is outside, the white tape mark is visible on the floor by their feet. (00:06:15)
The Joke's on Catwoman (2) - S3-E17
Visible crew/equipment: At the start, when the crime fighting trio split up Batgirl heads to her motorcycle, and when she attempts to start it two chalk T-marks are visible on the ground, one under the motorcycle in front of the rear tire and another beside the front tire. (00:00:35)
Visible crew/equipment: After Egghead dumps Batgirl into the vat of caviar, Egghead, Olga, and the Cossacks attempt to escape, then just as they run out the door, a bit of set lighting equipment (which wasn't in previous shots) is visible at the left side of the screen. (00:22:10)
Visible crew/equipment: While Batman and Batgirl are in the dungeon attempting to escape, it cuts to Alfred and Robin meeting up at the Batmobile at the same time, and the reflection of the diagonal boom pole is visible on the windshield. (00:16:15)
Revealing mistake: When Batgirl hands Batman the rope, just as he tells her to concentrate on the Indian fakir command, above Batman's head we can see the glistening wire that will be used in the stunt. Then, after Batman and Batgirl have escaped the dungeon Robin rushes up and asks how they did it, and when Batman reiterates the Indian fakir command for Robin, we can see the wire attached to the rope. (00:15:55 - 00:18:05)
Surf's Up! Joker's Under! - S3-E10
Visible crew/equipment: After Batman and Robin head out to Joker's hideout, when it cuts to Joker upon his success at stealing all of Skip's talent and vigor, just as Joker says, "You know what this means boys, the surfing championship," we can see the shadow of the boom mic moving at the far right side of the screen. (00:09:50)
How to Hatch a Dinosaur (2) - S3-E9
Visible crew/equipment: While Batman and Robin are in Commissioner Gordon's office Barbara reports the theft of the Neosaurus egg, and when Batman suspects it's connected to the radium theft, he and Robin decide to use the Batcomputer at the Batcave. Just as the Dynamic Duo rush to Gordon's door the camera turns to follow them, and we can see filming equipment at the right side of the screen as it tries to move out of view. (00:09:55)
How to Hatch a Dinosaur (2) - S3-E9
Visible crew/equipment: After Egghead tells Olga he's planning a three-course meal for the Neosaurus consisting of Batman, Robin, and Batgirl, and for dessert - Commissioner Gordon and Chief O'Hara. Then it cuts to the Batcave as Batman talks about the Bat-geiger, and when the camera moves closer we can see the camera movement's reflection on the windshield, at the bottom right corner of the screen. (00:15:15)
The Unkindest Tut of All - S3-E6
Deliberate mistake: When Batman has figured out King Tut's plot to steal ancient Egyptian scrolls from the Gotham City Library, he and Robin rush away, and in the shot of the library exterior, the words "The New York Public Library" is quite noticeable above the entryway. (00:18:00)
Continuity mistake: Batgirl's outfit includes boots with kitten heels, but during the fight scenes the stuntwoman's boots have block heels. (00:19:45 - 00:21:25)
Ring Around the Riddler - S3-E2
Continuity mistake: When Batgirl finds Betsy with the huge magnet under the boxing ring Batgirl throws the rope around the lever, then as the rope pulls the lever down the rope slips off and falls, but in the next shot the rope is still up around the lever. (00:21:25)
I'll Be a Mummy's Uncle - S3-E23
Plot hole: After the rock falls on King Tut at the end giving him amnesia, Batman explains how the rock fell. He says Tut raised his voice three decibels above high C. Decibels are a measure of volume, while pitch is a measure of frequency: the two are not directly related. This mistake was done in other episodes of Batman also, such as when Joan Collins played the villain.
Nora Clavicle and the Ladies' Crime Club - S3-E19
Revealing mistake: Not only does Batman's solo flute play two music tracks at once, it also keeps on playing after he's taken it out of his mouth. (00:20:00)
A Horse of Another Color (2) - S3-E5
Visible crew/equipment: The stunt rider doubling Penguin in the horse race is pretty easy to spot. He's younger and thinner (despite an obviously padded costume), and his nose is about two inches shorter. (00:18:00)
How to Hatch a Dinosaur (2) - S3-E9
Factual error: Gotham City's museum should brush up on its paleontology. Their sign claims the neosaurus egg is 40 million years old. A) Neosaurus lived in the early Permian period, 290 million years ago. And B) All dinosaurs were rendered extinct 65 million years ago, most likely by an asteroid strike. So 40 million years ago, there were no dinosaurs on Earth. (00:06:50)
The Joker's Flying Saucer - S3-E24
Continuity mistake: Batman and Robin both leap into the Batmobile and roar out of the Batcave. But the stock shot used after that shows Batman alone in the car. (00:03:10)






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