In 1905 Tom Longstaff and two Italian guides, the Brocherel brothers, set off to explore Nanda Devi - Longstaff's expeditions only ever involved a small number of people, each one carrying his own gear. They reached a high col just east of Nanda Devi's summit which is on the ridge of peaks surrounding the mountain itself but they were unable to descend to the Sanctuary. The Sanctuary is an area of about that is encircled by a ridge nowhere less than in height except for the Rishi Ganga gorge which had proved to be an insuperable obstacle. The Sanctuary, completely cut off from human intrusion, had become an area of immense interest to explorers and mountaineers. Two years later the same team returned along with Charles Bruce and succeeded in climbing Trisul, southwest of the Sanctuary, and this remained the highest summit to be climbed for twenty-three years. Their attempt to get into the Sanctuary had been impeded because, according to Tilman, though the map did credit to the maker's imagination it was apt to mislead.