An ancient route which in olden days served as a medium of trade, culture, tradition and religion between Spiti and Tibet. This is the trail, once walked by great gurus like Atisa, Dromton, Rin-chen-bZang-po and Padmasambhava ,resulting in the construction of many extraordinary monasteries such as Tabo, Kye, Kungri, Lalung, and Dhankar for the establishment of the Buddhist philosophy and way of life in Spiti. Trek starts from Kibber (4280Mts) in Spiti Valley and enters the Paralugui Gorge, This area comes under the Tectonic Thrust region and then further moves towards the ParaChu valley over Parang La (5600Mts)  and finally to the plains of Rupshu. Trek ends at Tsomoriri, the largest lake in Rupshu district from here there are possibilities of trekking further towards Tsokar on  the Manali – Leh road.