The Kingdom of Mustang had been a forbidden land until just recently. Famous for being an important salt trading post in the Trans Himalayan belt, even now the Upper Mustang is only opened for a limited number of trekkers. Lo Manthang (Mustang), located north of the main Himalayan chain bordering Tibet, is a stretch of dry and arid land with villages between the altitudes of 3,300m and 4,000m and passes not lower than 4600m. This is the route where you are likely to come across some very important historical sites. Just recently, an 800 year old cave and religious carvings have been discovered en route!