For a few years after the downfall of the USSR and before 9/11, there were public tours. That was a happy, peaceful time.
Here's a partial tour from the 1970s.[1]
There is no one big control room. There are about a half dozen control rooms with different functions. There are duplicate control rooms outside the mountain, and for a few years, those were primary and the mountain only had a skeleton staff. Not any more. (Although Hegseth apparently wants to move some operations to Huntsville, Alabama.)
Modern photos are available. Modest sized rooms with flat screens on the walls, desks, ordinary monitors, and keyboards. About the only unusual thing is that there's video switching, so that monitors can be copied to a big screen, or someone else's screen, when something is happening and many people need to focus on one screen.
There's now a vast flood of crap AI art and mislabeled clickbait for the Cheyenne Mountain Operations Center. Sorting out the real from the fake is becoming harder.
(One of my career achievements from my aerospace days was managing to avoid being transferred to Colorado Springs to work on their networking problems.)