Here is the note in context. Note the bridge plaque to the right of the sign. Also, note the shadow of the favorite building pictured in the previous daylight photos. The gaurd rail which trails off to the right leads to a highway entrance ramp, which accounts for the speed of the traffic on the bridge itself. I suppose people tend to forget they have left the interstate and entered a median arterial street. Pity them, for they will miss the fabulous views from the bridge.