scene of action vs arena

scene of action and arena both are nouns.

Word	Noun	Adjective	Verb	Adverb
scene of action	Yes	No	No	No
arena	Yes	No	No	No

As nouns, scene of action and arena are synonyms defined as:

scene of action and arena: a playing field where sports events take place

scene of action (noun)	arena (noun)
a playing field where sports events take place	a playing field where sports events take place
	a large structure for open-air sports or entertainments
	the central area of an ancient Roman amphitheater where contests and spectacles were held; especially an area that was strewn with sand
	a particular environment or walk of life