This is the famous St. Louis arch. It is 630 feet high and 630 feet across at the base. Airplanes have been know to fly under the arch as I understand it. It is however against the law.If you look very close, you can see a row of windows in the very top of the arch.They are very small but you are able to photograph through them if you place your lens against the glass. That's how I made some of the images in this gallery.