St. Louis Union Station is a National Historic Landmark opened in 1894. It was the largest American Rail Terminal from the turn of the century until the 1930's. It features a gold-leafed Grand Hall with Romanesque arches, a barrel-vaulted ceiling and Tiffany stained-glass windows. Architect Theodore C. Link designed the building based off inspiration from the city of Carcassone in southern France. Read more about the history of Union Station here.