Fastidious French resort (4)
I believe the answer is:
I believe this clue is a double definition.
'fastidious' is the first definition.
(similar in meaning)
'french resort' is the second definition.
(French coastal resort)
(Other definitions for nice that I've seen before include "City of southern France" , "Pleasant - exact" , "French resort; pleasing" , "French Mediterranean resort" , "Pleasant city in south of France" .)