10 Secret Rooms Inside Famous Landmarks

There's something inherently fascinating about hidden rooms—doubly so when they're hidden inside landmarks visited by thousands of people every day. Take Mount Rushmore, for example. The attraction, visited by more than three million people every year, boasts a secret room behind Abraham Lincoln's head. Gustave Eiffel, the designer of Paris's famous tower, created an apartment at the very top of the landmark.

And that's just the beginning. Read on for the coolest secret spaces within monuments.