South Korean artist Kimsooja has done one of the most amazing art installations I've seen. It's a 2006 project done in Palace de Cristal in Madrid.

This is how the exterior looks like. But when you go inside, wow.





He exploits the building's structure, while still keeping it intact, without any reconstruction or change to the structure. Instead, he installed a mirror to cover the entire length of the floor, to give that illusion of space and light from the reflections.

And for each of the glass paneled windows and walls, including the dome, he fixes a sheet of translucent diffraction grating film. It's quite a mouthful, but what this does is create a holographic rainbow effect whenever there's a light source. In this case, the sun. The sunlight is powerful enough to set off crazy, beautiful holographic effects, multiplied by the mirrors on the floor. The combination of all is pure genius, and simply beautiful.