Since mountain ranges can present formidable barriers to travel, passes have played a key role in trade, war, and both human and animal migration throughout history.
[2][3] On a topographic map, passes can be identified by contour lines with an hourglass shape, which indicates a low spot between two higher points.
Apart from offering relatively easy travel between valleys, passes also provide a route between two mountain tops with a minimum of descent.
As a result, it is common for tracks to meet at a pass; this often makes them convenient routes even when travelling between a summit and the valley floor.
[citation needed] In the highest mountain range in the world, the Himalayas, passes are denoted by the suffix "La" in Tibetan, Ladhakhi, and several other regional languages.
Scotland has the Gaelic term bealach (anglicised "balloch"), while Wales has the similar bwlch (both being insular Celtic languages).
One of the famous but non-motorable mountain passes is Thorong La at 5,416 metres (17,769 ft) in Annapurna Conservation Area, Nepal.