Opposing mirrors
Look into infinity. Look through the hole in the front wooden panel. Through the small holes in the opposing mirrors you see a long corridor that appears to be endless.
Through the small holes in the panel in front of you, you can see a long, seemingly endless corridor. What you are looking at through the hole is an image of the mirror that you are standing behind. A mirror reflects the light that hits it, which makes the light bounce back and forth between the opposing mirrors. How long the corridor appears to be depends on how much light there is and the eyesight of the person looking.