The Cathedral Basilica of Saint Louis

Built in 1907 the Cathedral Basilica of Saint Louis in St. Louis, MO boasts the largest collection of Byzantine mosaics in one place in the world. There are 41,500,000 pieces of tesserae (small piece of marble, tile or glass used in mosaic work) in more than 8000 shades of color. This adds up to 83,000 square feet of mosaic art. The mosaics were created and installed by 20 artists over a period of 75 years. The effect (as you can see in the above pictures) is breathtaking.