Helps at resort in mountain range (3,4)
I believe the answer is:
the alps
'mountain range' is the definition.
(the Alps is a kind of mountain range)
'helps at resort' is the wordplay.
'resort' is an anagram indicator.
'helps'+'at'='helpsat'
'helpsat' is an anagram of 'THE ALPS'.
'in' acts as a link.
(Other definitions for the alps that I've seen before include "natural barrier" , "Range" , "heights" .)