Cathedral Basilica of Saint Louis

The Cathedral Basilica of Saint Louis, generally known as the St. Louis Cathedral, or colloquially the New Cathedral, in Saint Louis, Missouri, was constructed in the early 20th century in the Central West End of the city, as the archdiocesan replacement for the Church of St. Louis IX, King of France (colloquially the Old Cathedral) on the historic St. Louis riverfront since 1770.

In 1912, installation of mosaics in the interior began. Completed in 1988, it contains 41.5 million glass tesserae pieces applying over 7,000 colors. Covering 83,000 square feet (8,000 m²), it is the largest mosaic collection in the world created by 20 different artists.