

Here, six keys to the architecture of terror: (A Fast Company colleague who visited the attraction years ago describes her experience this way: “my high school boyfriend ended up screaming in the fetal position.”) It doesn’t hurt that this particular haunted house is located inside a building that would be a little spooky even in broad daylight–a decaying 19th-century prison that reportedly drove its inhabitants insane through its use of solitary confinement. Now in its 24th season, the show uses a combination of animatronics, prosthetic flesh and boils for actors, and sheer surprise to properly terrify each and every visitor.

For answers, we turned to the creative team behind Terror Behind the Walls, a Philadelphia haunted house that’s regularly named one of the nation’s scariest and best.
