#6 Batman: Arkham Asylum – The Warden’s Secret Room
I think that the most impressive and mind blowing aspect to this secret room was that it took almost a year for someone discover it. In this digital era where virtually nothing is secret anymore, these kind of things are pretty much unheard of. So how did it defy those odds?
Well, the Warden's hidden office is located behind a destructible wall, but it does not show up in detective mode. Since every other object that can be interacted with does, it is no wonder that it took so long to be discovered.
The hidden room itself actually holds a pretty awesome secret: it contains an 'approved' blueprint for Arkham City, which wasn’t even close to being unannounced at that time.
