There are a lot of impressive buildings that I've been in that didn't have the impact I expected they would. But occasionally an unexpected one sneaks up on you. Union Station in St Louis turned out to be one of those. As soon as we walked in we couldn't help but let out a 'whoa.' The elaborate stained glass, surfaces and ornate treatments are not what you'd expect from the exterior. But what also is impressive is what a huge dark space it is with bright light streaming in from all angles. When it opened in 1894, it was the world's largest and busiest railroad station, and it expanded to be even larger for the 1904 Worlds Fair. The last train left its massive trainshed in 1978, and in 1985 it was converted to a hotel and mall. If you ever get the chance, be sure to take the time to wander through. You can't help but wonder about the days when it was in its height and the impression it made on travelers, though it still does that.