Mustang trek is a spectacular trekking experience of the concealed valleys of upper Mustang in Nepal, nestled between Tibet and the trans-Himalayas region of Nepal – a different place from rest of the world. In many ways, a trek into the upper Mustang is similar to trekking in Tibet, as geographically it is as a part of the Tibetan plateau. The goal of the Upper Mustang trek is the capital of Upper Mustang, Lo Manthang. From the pass Lo La (3950 m) you can see the walled medieval capital in the distance, the white-washed 6-meter tall unique wall sticking out in sharp contrast to the barren landscape. It is believed that Guru Rinpoche had fought with demon among the Mustang ‘s snowcapped mountain, desert canyons, and grassland. Once Guru Rinpoche killed the demon, it is said he scattered the demon’s body parts across Mustang valley: its blood formed the towering red cliffs and its intestines tumbled near to Ghami where people have later on build the stone prayer wall, the longest in Nepal, on top of the demon’s intestines. It was known as the Last Forbidden Kingdom until 1992 when foreigner was first permitted to enter the region. Now a day it is also popular as ‘Mini Tibet of Nepal’ or sometime as ‘Mountain Desert’. It lies in the Himalayan rain shadow and so is the one of the region in country suitable for trekking even during monsoons. The trail follows the ancient salt caravan route through which the people of Mustang traded Tibetan salt for grain from the lowlands. Special permit is required to enter this region, which makes this trek the most expensive trek in Nepal.