This secret door, featured on Reddit, was installed in an art gallery and let to a hidden studio. While it looks somewhat obvious, the room contains several trimmed areas like this, so the door blended in well. The top panel also housed a painting, with its own...
A recent Redditor found this secret bookcase door in a home he was living in, held closed by a nail in the bottom shelf. The hidden room behind contains a water heater, and access behind some walls.
