There’s an apartment inside the Eiffel Tower. When Gustave Eiffel designed the tower, he added a hidden apartment on the third level—but he never lived there, nor did anybody. Instead, Eiffel used this space to entertain guests such as Thomas Edison. Though it wasn’t big, the apartment was decorated with wallpaper, furnished with wooden cabinets, and even had a grand piano. Nowadays, you can get a peek at the unique space through a window if you ride up the tower.