The confluence of the Rangeet and Teesta rivers, in Darjeeling’s Teesta Bazaar. The Teesta is on the right. t the top of the Himalayas in Sikkim, from the waters of the Khangse and Zemu glaciers that feed the Tso Lhamo lake in a high plateau just north-east of the mighty Kanchenjunga, the Teesta springs to life.