What do vienna, warsaw, london, cologne, and paris have in common? view available hint(s) what do vienna, warsaw, london, cologne, and paris have in common? they are all at the same elevation. they are all capital cities. they are all located on some of europe's major rivers. all of these cities are at the center of a metropolitan area of 10 to 20 million people. they are all located along the southern limit of pleistocene glaciation?