metropolis vs Kingston upon Hull

metropolis and Kingston upon Hull both are nouns.

Word	Noun	Adjective	Verb	Adverb
metropolis	Yes	No	No	No
Kingston upon Hull	Yes	No	No	No

metropolis (noun)	Kingston upon Hull (noun)
people living in a large densely populated municipality	a large fishing port in northeastern England
a large and densely populated urban area; may include several independent administrative districts