Mustang, or Lo as it is known by the inhabitants, is a mysterious high plateau tucked behind the Annapurna and Dhaulagiri Massifs in north central Nepal . The area is actually the top of a watershed, the headwaters of what becomes the mighty Kali Gandaki River , which then runs southward through the world's deepest gorge. In the rain shadow of the huge Himalayan peaks, though, this area is dry and windswept, ruggedly sculpted and mostly devoid of vegetation. The region offers dramatic and unique geography for those who only have seen the more familiar green, forested landscape of the rest of Nepal . This area has piqued the curiosity of many Himalayan adventurers, and only recently was it opened for limited visitation. Historically a vital trading route between Tibet and India , the trail into Mustang is lined with the fascinating remains of forts that served as tax collection out posts. Settlements in Mustang were fortified, a testament to its turbulent history. More recently, in the late 1950s and 60s, the area was a center for Khampas, guerrilla's who were trained and armed by the US C.I.A. to resist the Chinese Army's occupation of Tibet.

There are records that outline events stretching back to the eighth century, and from the writings of the Tibetan poet Milarepa it is known that the unique form of Buddhism called Sakyapa has been practiced here since 1073. This form of Buddhism lacks the more familiar metaphysical aspect; it is more worldly and practical, perhaps in response to the unforgiving environmental pressures in this area. Throughout recent decades, the Nepalese had maintained total restriction on visitation to this area. The democratic change of government of 1990 and the increasing international pressures for a more open Nepal have coincided to remove these restrictions.

Since 1991, limited visitation has been allowed, providing the trekking party meets strict environmental requirements and pays a substantial amount for the entry permit. These conditions limit the number of visitors, minimize their impact, and generate revenues needed for future conservation efforts in this region. Given the remoteness of this trekking area, the logistics of the trip are some what complex. While the trekkers can fly into Jomosom (at the north end of the Kali Gandaki Valley ), food, cooking fuel and other provisions must be carried by porters up from Pokhara. The trekking party may move north for a day or so on foot, then (usually at Kagbeni) the loads are transferred to horses which are usually managed by Lobas, the people of Mustang. The trekking route stays mostly on the valley floor, though it may traverse the ridge during the occasional rainy period, which raises the level of the river. The horses provide uphill assistance, but must be dismounted for descending. Without substantially high passes (nothing over 5.000 meters) this is not too physically demanding as a trek, and it has the added advantage of a very long season, due to the lack of monsoon rains or high pass crossings. Mustang's capital "city" is Lo Manthang, a magical place imbibed with centuries of rugged history. Set on a broad plateau, the town deserves its name, which translates from Tibetan as "plain of inspiration". The Raja, or King, lives in his palace in the center, while the four major temples form the corners of town. Lo Manthang and the surrounding area are usually savoured for a day or two before heading back down toward Jomosom.