Historic county of Northern Ireland famous for the Giant's Causeway (6)

I believe the answer is:

antrim

(Other definitions for antrim that I've seen before include "County of northeast Ireland" , "N Ireland county of green glens" , "Irish county of musically green glens" , "County in Ireland's north-east" , "Giant's Causeway county" .)

I've seen this clue in The Mirror.

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