mountain pass

In a range of hills, or especially of mountains, a pass (also gap, notch, col, saddle, bwlch or bealach) is a lower point that allows easier access through a range. On the route through the range, it is locally the highest point on the route. Since many of the world's mountain ranges have always presented formidable barriers to travel, passes have been important since before recorded history, and have played a key role in trade, war and migration.
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Noun
1. the location in a range of mountains of a geological formation that is lower than the surrounding peaks; "we got through the pass before it started to snow"
(synonym) pass, notch
(hypernym) location
(hyponym) Brenner Pass
(part-holonym) range, mountain range, range of mountains, chain, mountain chain, chain of mountains