Another side trip from Auburn Indiana was to Spencerville, De Kalb County, Indiana, to see the covered bridge. This is also on the National Register of Historic Places.
This web address gives some details and photos about the bridge:
I drove across the bridge. It is over St. Joseph's River, a wide enough river that apparently has some good fishing spots as well as a place to put a boat in. I could see upstream a small rapids, and looking downstream a more peaceful meander of water around a bend. I stayed in the parking area for a bit and listened to the sounds of nature, feeling right at home.