I never expected to see a cathedral like this in St. Louis, Missouri. Completed in 1914 this spectacular building would be a natural in some European capital, but a surprise in the heart of the U.S. From a distance, the walls and ceiling of this cathedral look painted. With a closer look you see that they are covered in 41.5 million glass pieces in more than 7,000 colors. Covering 83,000 square feet, it is the largest mosaic collection in the world. More than intricate, it’s staggering. These photos are just a sample.