Here is a link to an article about the bridge http://www.lexingtonillinoisfort.org/Articles/2005/August/RainbowBridge.htm
I added this a couple years ago and am glad to see it still exists. A truly hidden gem that needs a new lease on life. The county had talked of making this area into a park several years ago...but unfortunately that never came to fruition.
Imagery withing the link: http://www.advrider.com/forums/showthread.php?t=690215