Kim Mensinger has sent in some nice photos of a couple of  the historic bridges on the Cannon Bottom Road, just west of Red Wing, which was bypassed in 1931 (it was once part of U.S. 61 and Constitutional Route 3). These bridges are scheduled to be demolished in the next few years. For more info on this historic highway, see the article here (from my U.S. 61 project, pops in a new window/tab).