Motorway bridge without a motorway: This is how the lonely structure near Euskirchen came about. The bridge between Frauenberg and Elsig was planned in the 1970s as part of Autobahn 56 - but it was never completed.
The unfinished structure was not demolished - and so the bridge remains lonely and pretty useless in the landscape to this day. A dirt road leads under the “dead bridge’s “So-da-Brücke”