The Gateway Arch is part of the Jefferson National Expansion Memorial. The JNEM was declared a National Historic Monument on 12/21/1935 to commemorate several historic events:
1. The Louisiana Purchase and subsequent western expansion of the USA and the movement of American explorers and pioneers
2. The first civil government West of the Mississippi River
3. The debate over slavery raised by the Dred Scott case (originated in the St. Louis area where Dred Scott lived with his wife and "master")
The Gateway Arch is the tallest man-made national monument in the USA. The width of its legs at the base is equal to its height (630 ft). It took 900 tons of stainless steel and 17,246 tons of material in all to construct the arch. The shape follows what is known as a "catenary curve" - the formation that the slack of a chain would take if it were held at both ends. Construction on the legs of the arch was begun simultaneously on 02/12/1963 and in order for the arc to meet in the middle the margin of error was less than 1/64th of an inch. In high gusts of wind (150 mph) the arch has been known to sway up to 9 inches both ways. The normal sway for the arch is about 1/2 inch either way.
For all of you Michiganders out there - you should know that the architect that designed the arch was a man by the name of Eero Saarinen. Eero was the son of Eliel Saarinen who emigrated to the USA in 1923 to design the grounds, and instruct for the Cranbrook Institute of Arts in Bloomfield Hills, MI. Eero was 13 in 1923 and spent his first years in the USA in Bloomfield Hills. Wikipedia lists that Eero died in Ann Arbor, MI - but I have not been able to verify this fact just yet.
We were pretty lazy yesterday and as a result did not get to the Arch until later in the day. I am glad that it worked out this way because I was able to take some night pictures. I did not go to the museum *surprise* because I was too busy taking pictures. Due to the low light the pictures were averaging about 20 seconds for each exposure, and that adds up quickly. We did not go up in the tram either *not-surprise*. Besides the fact that it is a tight fit, long ride, and scary - Tri-pods are not allowed and without my tri-pod I can't take night pictures. It would have been fun, but I would rather wait until my next visit when I can take decent pictures from the height.
Speaking of next visit - did you know that when you visit the JNEM you can: Take a riverboat cruise, helicopter tour, visit the Museum of Westward Expansion, visit the historic courthouse, and watch large format movies? I can't wait to come back!
Wikipedia: The Gateway Arch