Construction for The Cathedral Basilica of St. Louis began in 1907 and was completed in 1914.  It contains the largest mosaic collection in the world, composed of over 41 million pieces of glass.  The mosaic was started in 1912 and was completed in 1988.  It covers over 83,000 square feet.  The mosaics tell the story of Catholic Faith from creation to the last judgment.  There is a large dome in the center and two smaller domes on the ends.  It is a magnificent work of architecture to see.   The Cathedral is open most days and guided tours can be arranged as well.  

This is a view of the sanctuary in the Old Cathedral. Construction of the Cathedral began in 1831 and was completed in 1834.  It was the first Cathedral west of the Mississippi River.  It was the first Cathedral of the Archdiocese of St. Louis and was used until the current cathedral (mentioned above) was completed in 1914.  In 1933, the land surrounding it was purchased and designated for the Jefferson National Expansion Memorial park.  The former cathedral was the only building and piece of land in the vicinity not to be claimed for the park.   It was named a Basilica by Pope John the XXIII in 1961.