<a href="https://en.wikipedia.org/wiki/DBAG_Class_644" class="extiw" title="w:DBAG Class 644">DBAG Class 644</a> multiple unit train no. 644 037 operating as a <a href="https://en.wikipedia.org/wiki/DB_Regio" class="extiw" title="w:DB Regio">DB Regio</a> service at <a href="https://en.wikipedia.org/wiki/K%C3%B6ln_Hauptbahnhof" class="extiw" title="w:Köln Hauptbahnhof">Köln Hauptbahnhof</a>, Cologne, Germany
<a href="//commons.wikimedia.org/wiki/User:Bahnfrend" title="User:Bahnfrend">Bahnfrend</a>
CC BY-SA 4.0
<span class="int-own-work" lang="en">Own work</span>