The Zanskar range in large part marks the divide and Tibet. Running broadly north- west to south -east it offers few points of passage. Up north between Spiti and Ladakh, where an off shoot connects the himalaya and the zanskar ranges ,are two high passes crossing from the upper parechu to the main spiti valley. over the centuries, traders from Rupshu and Changthang areas of ladakh used these passes to attend the famous barter trade fair of ladarcha in Spiti, sadly despite a good background, the passes are little used today. Although the trek is good enough to satisfy serious trekkers, the main attraction of this trek is Tsomoriri lake( 4,573m); 30km long and 8km wide, this is the only trek joining the barren lands of Ladakh and Spiti.