San Bernardino vs metropolis

San Bernardino and metropolis both are nouns.

Word	Noun	Adjective	Verb	Adverb
San Bernardino	Yes	No	No	No
metropolis	Yes	No	No	No

San Bernardino (noun)	metropolis (noun)
a city in southern California to the east of Los Angeles	people living in a large densely populated municipality
	a large and densely populated urban area; may include several independent administrative districts