The enigma of the Sanctuary naturally attracted the attention of European explorers and mountaineers of the nineteenth and early twentieth century, but a route over the walls of mountains surrounding the Nanda Devi Sanctuary appeared to be impossible. The problem was finally solved by Eric Shipton and Bill Tilman in 1934 in the first of their great Himalayan expeditions. They forced a way up a river gorge and became the first human beings to set foot in the Sanctuary.

Above them was the towering spire of Nanda Devi itself, 10,000ft above the amphitheatre. Herds of blue sheep who had never seen humans before grazed on pastures full of alpine flowers. There were wild snow leopards and bears who were equally unafraid of man. This exploit of exploration was followed by Tilman's successful ascent of Nanda Devi in 1936.

The onset of war soon afterwards meant that the Sanctuary remained un-visited for a number of years, and was then closed to travellers for political reasons right up until the seventies, when a brief window opened for expeditions. However in 1983 the Indian government again closed the Sanctuary. The delicate ecology of this hitherto pristine space needed time to regenerate after the inevitable damage caused even by the few expeditions and shepherds who were able to find their way in.

Now twenty years later the Sanctuary has again just been entered by an expedition led jointly by Eric Shipton’s son, John Shipton, and the great Indian mountaineer Colonel Narinder Kumar, who as a young man led the first successful Indian ascent of Nanda Devi. Together with Steve Berry of Himalayan Kingdoms, they managed to secure permission from the Indian Government for an exception to the previously iron-clad rule that no one may enter the Sanctuary.

Hugh Thomson was lucky enough to join this quite unique expedition, which recaptured some of the exhilaration felt by Shipton and Tilman when they first saw it in 1934 - the feeling of entering a lost world.

As he did in The White Rock, Thomson weaves the story of his own journey together with those who have gone before him, giving a tantalising account of a place one explorer described as ‘more inaccessible than the North Pole’.

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