Cartagena vs urban center

Cartagena and urban center both are nouns.

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

Cartagena (noun)	urban center (noun)
a port in southeastern Spain on the Mediterranean	a large and densely populated urban area; may include several independent administrative districts
a port city in northwestern Colombia on the Caribbean