Gotham City Map
The “Giant Lighted Lucite Map Of Gotham City” which appears in many episodes is, in fact, a map of St. Louis, Missouri. It even includes several landmarks of the city like Tower Grove Park, Forest Park, and Lafayette Park.
Opening The Batcave
The door that led to the Batcave opened when Batman pressed a secret button on Shakespeare’s bust. That button didn’t actually open the door itself, but it was linked to a light backstage that alerted the stage crew to open the door.