Borasu Pass divides Uttarakhand from Himachal Pradesh. The pass is located only a few kilometers from the Tibet border. The east part of the Borasu area comes out from Tons valley and the north-west part is merged with Baspa valley. Its north-west range comes down on Jhukia Glacier. The nearest village, Chitkul, is 20.3 km (12.6 mi)away from the pass.[2] on the Himachal Pradesh (Kinnaur valley) side and Osla village on the Uttarakhand side of the pass.
In summer, temperatures range from 0 °C (32 °F) to more lower. After November, the temperature falls down to several degree lower from 0 °C (32 °F). Precipitation in Baspa Valley is low in scale. Comparatively in the side of Tons valley rainfall is often common. Generally, snowfall is received after October.