Mountain __ (4)
'mountain' is the definition.
(the Alps are a mountain range)
This is all the clue.
(Other definitions for alp that I've seen before include "Swiss mountain" , "Mont Blanc, for example" , "Mountain pasture" , "High mountain" , "high point" .)
(Other definitions for pass that I've seen before include "Mountain road" , "gap" , "entry document" , "Go beyond; fail to answer" , "Blow over" .)