metropolis vs Krakow

metropolis and Krakow both are nouns.

Word	Noun	Adjective	Verb	Adverb
metropolis	Yes	No	No	No
Krakow	Yes	No	No	No

metropolis (noun)	Krakow (noun)
people living in a large densely populated municipality	an industrial city in southern Poland on the Vistula
a large and densely populated urban area; may include several independent administrative districts