The monasteries were built by Mustang's indigenous Loba people during the kingdom's 15th century heyday. The murals they housed, Tibetan-style depictions of Buddhist gods and mythological creatures, had mainly ritual functions but were in such bad shape that they were no longer worshipped by the locals.
The murals had collected layers of grime and soot and had lost their original vibrancy. The monasteries had been rocked by earthquakes and let in water that caused massive damage.
Luigi Fieni leads the restoration work by the American Himalayan Foundation, a US-based non-profit that helps preserve Himalayan cultures, and describes what he saw when he first encountered the murals in 2001. "Water infiltrations had washed away part of the pictorial cycle, and rising dampness had eroded and destroyed the lower sections of the murals. In some of the worst cases, the wall paintings were detached a couple of inches away from the wall, ready to fall off."
The Foundation trained over 100 indigenous local carpenters and artisans to restore the monasteries, and they hope they will manage their upkeep in the decades to home. Luigi's workers have been joined by other conservation groups, including NOVA, and local non-profits run by members of Mustang's former royalty.
Work has focused on the bigger gompas like Thubchen, Jampa, Ghar and Tsarang and has involved advanced restoration techniques (see box). So far, the work has gone brilliantly, but conservationists insist the results are about much more than brick and mortar.
"More important than that, the Loba community acknowledged the importance of their own cultural heritage, something they are really proud of now," says Fieni.
When restoration work began in Lo Manthang's Thubchen monastery in 2001, the once-vivid colours of its wall paintings appeared dull and grimy, trapped behind 500 years of smoke, soot, and grease from butter lamps, and large pieces of these medieval masterpieces hung precariously off the walls.
But the restoration team worked wonders, returning Thubchen's surviving wall paintings to remarkably close approximations of their original magnificence.
In order to repair the paintings, head conservator Rodolfo Lujan and his team began a painstaking process. First, they carefully cleaned the paintings to ensure that only the painting's surface dirt ? and not its pigments, made of semiprecious stone ? came off.
Once the paintings were clean, the team began to secure loose pieces of the murals using plaster made from mud and a powerful adhesive.
The final step in restoration involved touching up areas of the paintings where colour was missing due to extreme damage. To preserve the integrity of the original paintings, Lujan's team used washable watercolour paints in crosshatched strokes.
The ongoing restoration of the paintings in Thubchen, along with the structural renovations to the monastery's roof and beams, should help ensure that these treasures will remain intact for another 500 years.