Pals wandering in mountains (4)
I believe the answer is:
alps
'mountains' is the definition.
(European mountain range)
'pals wandering' is the wordplay.
'wandering' indicates anagramming the letters.
'pals' is an anagram of 'ALPS'.
'in' acts as a link.
(Other definitions for alps that I've seen before include "European mountains" , "Peaks" , "Mont Blanc is therein" , "& 11 their highest peak" , "Eur. mountain range" .)