The lack of local knowledge about the towers’ origin could be due to the region’s history and geography. The region where the towers are found has been historically occupied by different mountain tribes who have maintained isolation for centuries. Due to the diverse nature of their origins and the fragmented terrain in which they live, the languages and dialects they speak are vastly different from one another. “Even from one valley to the next, the locals couldn’t speak to each other,” Darragon says in a documentary titled Secret Towers of the Himalayas, produced by her friend Michel Peissel. Darragon believes that knowledge of the towers might have been previously passed down through oral tradition, but now forgotten as dialects changed or vanished.

Himalayan towers depicted in a painting of the Jinchuan campaigns.

These monumental structures were built using a mixture of cut stone, brick, and timber and come in various shapes including square, polygon, and star-shaped with up to 12 vertices. They contain very little mortar and due to the wooded planks and beams that intersperse between the stones, these robust constructions are able to absorb the force of violent shaking that accompany earthquakes. Especially the star-shaped construction that make the structures less susceptible to tremors.

By conducting radiocarbon dating of the wood in the towers, Darragon determined that these towers are between 600 to 1,000 years old. Darragon believes the towers did not serve a single purpose, but its use differed from valley to valley. In Miniak, for example, she believes that many were watchtowers. She bases her conclusions upon such observations like the entrance being several stories above the ground, and the location of the towers where trade routes met. In Kongpo and Damba, the towers seem to be primarily symbols of wealth and pride. According to one tale, the towers were built by locals who grew rich by trading with Mongol-ruled China.

Many of the towers are now in a derelict state. Darragon is working to get the towers listed under UNESCO’s World Heritage Site. The designation would likely help protect the towers and raise money to restore them. She is also trying to enlist Sichuan University’s help in studying the structures. In 2006, the stone towers were placed on the watch list of the World’s Monument Fund, a non-profit organization dedicated to the preservation of historic architecture and cultural heritage sites around the world.