Saragossa vs urban center

Saragossa and urban center both are nouns.

Word	Noun	Adjective	Verb	Adverb
Saragossa	Yes	No	No	No
urban center	Yes	No	No	No

Saragossa (noun)	urban center (noun)
an ancient city on the Ebro River in northeastern Spain; formerly the capital of Aragon	a large and densely populated urban area; may include several independent administrative districts