Zorkul (or Sir-i-kol) is a lake in the Pamir Mountains. It extends east to west for about 25 km. The Afghan-Tajik border runs along the lake from east to west, turning south towards Concord Peak (5,469 m), about 15 km south of the lake. The lake's northern half lies in Tajikistan. Out of the lake, towards the west, flows the Pamir River, tracing the Afghan-Tajik border. It is therefore a source of the Amu Darya or Oxus River. The lake was once in the territory of the emir of Wakhan, but the lak… (More on Zorkul)