A section of the stained glass windows on the cool side of Sagrada Familia church in Barcelona. The stained glass, on one side of the church, is all cool tones while those on the other side are all in warm tones.I think Gaudi's idea was to balance out the type of light that came into the church at different times of the day. The whole wall of stained glass windows is vast and breath taking, this is just one section. More effective on black.
