I&#x27;m not entirely convinced either way.<p>Look at the Ruhr region. Like all German cities the cities in the Ruhr region have their own identities which the locals are very attached to and their own differences and rivalries. But to outsiders moving in it&#x27;s all one contiguous region and this is exactly the direction politics is taking the region (with things like the Ruhr University which has merged the various local universities into a single distributed entity).<p>I don&#x27;t see Cologne swallowing Bonn or even Leverkusen anytime soon (or in Leverkusen&#x27;s case: swallowing it <i>again</i>) but given enough time (and in comparison with the total age of the cities even a hundred years isn&#x27;t much) it might happen eventually.<p>That said, I&#x27;m a Cologne native who recently moved into a small city in Westphalia and am still amazed how many major companies have their headquarters in the region despite having theoretically outgrown their home towns.<p>As far as I can tell, Germany seems to define itself in terms of regions as you say. Whether those regions will eventually grow into megacities or merely &quot;polycentric urban areas&quot; (as Wikipedia describes the Ruhr region) is ultimately philosophical.