Streckennetz der Köln-Bonner Eisenbahn ca. 1975
The original uploader was <a href="https://en.wikipedia.org/wiki/de:User:Qualle" class="extiw" title="w:de:User:Qualle">Qualle</a> at <a href="https://en.wikipedia.org/wiki/de:" class="extiw" title="w:de:">German Wikipedia</a>.
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<span class="int-own-work" lang="">Own work by the original uploader</span>