18. Hidden Mirror Vault
This is the best place to keep that stack of cash or gold bars you don’t want the Uncle Sam to get their hands on! Oh, and you can easily use it to partake in your beauty!
17. Anne Frank’s Hidden Bookcase
This is one of the most famous hidden doors in history (at least to us). Anne Frank and her family were able to hide from Nazis during WWII for up to two years due to a hidden apartment behind a bookcase.