Parthenon Secret: Optical Illusion
Architects Callicrates and Ictinus were really good at understanding how the human eye works when such a large building is constructed. From a distance, the columns of the Parthenon appear to be perfectly straight, balanced, and without deviation. But they are not. Imperfections in the human eye would make the columns appear distorted. To correct for this, architects made the columns a few inches wider in the middle. Because of this, people standing next to the columns would see them as perfectly straight, and reaching to the sky. Inside the temple, the large, open floor has a very slight, virtually invisible dip to make it look perfectly flat.