I was with a team travelling incognito inside a freight car of a train, oh, for maybe a half hour or so, to a train yard outside the city (whatever city that might have been).
We walked off the train and across the platform to a heavy iron door, which someone unlocked (I was viewing this from the inside). The door led into a cave inside the mountain just off to the side of the platform.
We had entered the Bat Cave! Fancy computers, high tech gizmos… I was even vaguely aware in the dream of the nearby presence of a batmobile, although I didn’t see it!
No, we were not Batmen or Robin, but some other sort of specialized team with a specific mission which as not clear from the content of the brief dream. Anyhow, that’s all I remember!