Lachulung La or Lāchālūng La or Lungalacha La, is a mountain pass along the Leh-Manali highway

Leh-Manali Highway

The Leh-Manali Highway is a highway in India connecting Leh and Manali. It is open only between June and mid-September when snow is cleared from the road by the Border Roads Organisation. It connects the Manali valley to Kullu valley, Lahaul and Spiti and Ladakh...

. It is located some 54 km (33.6 mi) from Sarchu

Sarchu

Sarchu , a tented camp in the Himalayas on the Leh-Manali Highway, on the boundary between Himachal Pradesh and Ladakh in India...

 and 24 km (14.9 mi) from Pang on the Leh-Manali highway.

This is one of the easier 16000 ft (4,876.8 m) passes and it can be traversed cross-country by moving along the nala on both sides. However, due to elevation, the hikers face breathlessness during climb and those who have not undergone acclimatisation may face severe symptoms of altitude sickness

Altitude sickness

Altitude sickness—also known as acute mountain sickness , altitude illness, hypobaropathy, or soroche—is a pathological effect of high altitude on humans, caused by acute exposure to low partial pressure of oxygen at high altitude...

.