Kalapaani (कालापानी) is an area under territorial dispute[1][2] in Darchula District, Nepal and Pithoragarh district of India. The origin of Kali River, it is situated on the Kailash Mansarovar route, at an altitude of 3600 meters. It is said that the Great Sage Vyasa meditated at this place, giving the region its name - Vyasa valley, locally called Byans valley. A pool by the temple of the Goddess Kali is considered to be the source of the Kali River. A verdant valley covered with Pine, Bhojpatra and Juniper trees, it offers stunning views of some of the lesser known peaks like Om Parvat in the Central Himalayas.Lipu-Lekh Pass leading into Tibet is 17 kilometers from Kalapaani.
Although claimed by Nepal, Kalapaani is currently being occupied by India's Indo-Tibetan border security forces [2] since the 1962 border war with China. Nepal claims that the river to the west of Kalapani is main Kali, hence it belongs to Nepal. But India claims that river to the east of Kalapani is the main Kali river, hence Kalapani area belongs to India. The river borders the Nepalese zone of Mahakali and the Indian state of Uttarakhand. The Sugauli Treaty signed by Nepal and British India in 1816 locates the Kali River as Nepal's western boundary with India.[2] Subsequent maps drawn by British surveyors show the source of the boundary river at different places. This discrepancy in locating the source of the river led to boundary disputes between India and Nepal, with each country producing maps supporting their own claims. The Kalapani River runs through an area that includes a disputed area of about 400 km² [1] around the source of the river although the exact size of the disputed area varies from source to source.[3]