Question

What is the meaning of hairpin mountains ??​

Answer 1

Explanation:

Hairpin turns are often built when a route climbs up or down a steep slope, so that it can travel mostly across the slope with only moderate steepness, and are often arrayed in a zigzag pattern.

Answer 2

 hairpin turn, named for its resemblance to a hairpin/bobby pin, is a bend in a road with a very acute inner angle, making it necessary for an oncoming vehicle to turn about 180° to continue on the road. Such turns in ramps and trails may be called switchbacks in American English, by analogy with switchback railways.