Gipmochi

Gipmochi (Gyemo Chen or Gamochen, 'The Great Queen') is a mountain in the Lower Himalayas in south central Asia. Rising to a height of 14,523 feet (4,427 m), the mountain sits on the border between the northern Indian state of Sikkim and Bhutan, at China's claimed tri-junction point. Bhutan and India, however, claim that the tri-junction point is 6.5 km to the north, at Batang La.

The Imperial Gazetteer of India states that the Dongkya range (or Chola range) that divides Sikkim from the Chumbi Valley bifurncates at Gipmochi into two great spurs, one running to the south-east and the other to the south-west. Between the two spurs lies the valley of the Dichul (Jaldhaka) river. The "western shoulder" of Gipmochi was said to contain the trijunction point of Sikkim, Bhutan and Tibet. The southwest spur mentioned in the Gazetteer forms part of the boundary between Sikkim and Bhutan. The southeast spur, called the Jampheri ridge (or Zornpelri ridge), currently separates the Bhutanese districts of Haa (to the north) and Samtse (to the south).

The area bounded by Gipmochi and Batang La, extending about 5 km to the southeast, forms a plateau called Dolam or Doklam plateau. Some British maps from the 19th century mark this plateau as "Gipmochi Pla[teau]" and show its alignment with the Sinchela pass (on the northern ridge of the plateau). Bhutan did not have a map of its lands till 1961.

The Chinese claim of the trijunction point is based on the 1890 Anglo-Chinese Convention, Article I of which states:

The boundary of Sikkim and Tibet shall be the crest of the mountain range separating the waters flowing into the Sikkim Teesta and its affluents from the waters flowing into the Tibetan Mochu and northwards into other rivers of Tibet. The line commences at Mount Gipmochi on the Bhutan frontier and follows the above-mentioned waterparting to the point where it meets Nipal territory.

The Article explicitly states Gipmochi as being the China-India-Bhutan tri-junction for the borders, but does not state any other details regarding Bhutan. Bhutan was not a signatory to the Convention. Further, Gipmochi is not the highest point on the Doklam plateau. Merug La, at 15,266 feet, and Sinchela, at 14,531 feet, are higher, making the Batang La–Merug La–Sinchela line the highest watershed in the region.

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