Many are the mysteries that skulk quietly behind the desolate beauty of the Himalayas. Entire caravans of travellers have vanished, and creatures unknown to science are said to stalk the inhospitable heights where knifing wind and altitude sickness can kill strong men in hours.
But science can sometimes persuade the spirits of the mountains to yield up their secrets. One of the most well-known mysteries of the Indian Himalayas has been that of the skeletons of Roopkund, a lake 5,054 metres up in Uttaranchal's Garhwal region. In 1942, a forest ranger uncovered what appeared to be a mass grave at the lake. The discovery of hundreds of skeletons sparked intense speculation. Was it mass suicide? Or were they pilgrims, Tibetan traders, even Firoz Shah Tughlaq's lost army?