This page has some links to various articles involving the Stone Arch Bridge. I added a few other links about nearby areas as well.
A much more comprehensive tour of the area. Probably more factual that my tour.
Wiki Article on the Stone Arch Bridge
A video for those of you who hate reading
Another good history from Mnopedia.org
MinnPost story (lots of good pictures)
KARE11 TV (again for those who don't like to read)
BringMeTheNews.com story with pics