The Imperial Gazetteer of India states that the Dongkya range (or Chola range) that divides Sikkim from the Chumbi Valley bifurcates 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 Zompelri ridge (or Jampheri ridge), currently separates the Bhutanese districts of Haa (to the north) and Samtse (to the south).