Strasbourg vs Strassburg

Strasbourg and Strassburg both are nouns.

Word	Noun	Adjective	Verb	Adverb
Strasbourg	Yes	No	No	No
Strassburg	Yes	No	No	No

As nouns, Strasbourg and Strassburg are synonyms defined as:

Strasbourg and Strassburg: city on the Rhine in eastern France near the German border; an inland port

Strasbourg (noun)	Strassburg (noun)
city on the Rhine in eastern France near the German border; an inland port	city on the Rhine in eastern France near the German border; an inland port