urban center vs Zaragoza

urban center and Zaragoza both are nouns.

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

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