The Suru and Zanskar valleys form a great trough at the foot of the northern, heavily glaciated flank of the Himalayas, while opposite rise the mountains of the Zanskar range. The Suru River forms the western and northern boundary of the Zanskar range. The Suru, after receiving the combined waters of the Dras and Shingo Rivers a short distance north of Kargil, joins the Indus at Marol in Baltistan, which is now on the Pakistan side of the Line of Control. Rangdum Monastery and the attendant village of Julidok is the last inhabited region in the Suru valley; it is also the destination of the nomadic herdspeople called Bakarwals, who trek up every summer from the Jammu region. From Rangdum the valley rises to 4400 metres at the Pensi-la, the gateway into Zanskar. Kargil, the only town in the Suru valley, was an important staging post on the routes of the trade caravans before 1947, being more or less equidistant, at about 230 kilometres from Srinagar, Leh, Skardo, and Padum. Rangdum, though on the northern side of the Pensi-la, is regarded as socially and culturally part of Zangskar rather than of Suru.