I resided in the Werl area in the 1980s and was intrigued by a street near Werl station called "An Kleinbahn". Embedded in the road near the level crossing were three rails long disused. It looked like dual standard and narrow gauge. I can find nothing in English but I found the following link which my German is too poor to make much sense of. Was this disused track in the road part of a system mentioned in the internet article?