THE Chiba University Expedition to Mt. Numbur (22,817 feet), 1 which is located to the south-west of Mt. Everest, was organized from March to July, 1963. Besides attempting to climb Mt. Numbur, the expedition also undertook an ecological survey in the Junbesi area. This report deals only with the mountaineering aspect.

The party left Kathmandu on April 18, 1963, and arrived at Junbesi, which is on the route to Everest, on April 29. From Banepa the mountaineering equipment, food and other stores were transported by 75 ordinary porters with four high-altitude porters and five local porters.

The mountaineering party consisted of four members: K. Suzuki (sub-leader), K. Shimada, H. Matsuo and a Swiss guest, Mr. A. P. Hirsbrunner, from Jiri Hospital. Three high-altitude porters and four local porters were recruited to support the climbing team. The climbing team left Junbesi on May 1 and established their Base Camp near the origin of the Solu Khola at a height of approximately 4,000 metres. On May 5 Camp I was erected at a height of 4,600 metres near the upper stream of the Beni Khola. In order to reach Camp I the party crossed the South ridge and most of the equipment was moved from Base Camp to Camp I, which thereafter functioned as a de facto Base Camp. From Camp I there was a clear view of the upper part of Mt. Numbur and it was possible to work out a practical route on to the upper part of the South ridge.

Camp II was established on May 10 at a height of 4,600 metres on the Dudh Kund and Camp III was placed on the glacier directly under Mt. Numbur five days later. From Camp III the route led up the steep couloir followed by a rock and ice-wall on to the South ridge. On this section three 200 metres fixed ropes were used. Camp IV was finally sited at 5,600 metres on May 17. Camp III was used as an advanced Base Camp and there were daily carries of food and equipment from Camp III to Camp IV.

It was decided to place one more camp from which the summit would be attempted but, although attempts to find a route started on May 18, great difficulty was experienced. Above Camp IV there was a 600-metre high ice-wall with an average angle of 60°. Half of the wall consisted of very hard blue ice. All the climbers took turns at cutting steps and fixing ropes on the wall. The work was very laborious and sometimes they only advanced 50 metres. The route was protected with 400 metres of fixed rope and some 30 ice pitons. The attack on the blue ice-wall lasted up to May 22. The weather during this period was comparatively good, although strong winds and snow were experienced during the evenings. The monsoons had already started and the weather grew continuously worse from May 23 onwards. Daily attempts were made to push on beyond the ice-wall but violent winds and snow made it impossible to regain the top of the wall. By May 26 the food supply of Camp IV had dwindled to only three days' supply. The next day Hiroshi Matsuo and Mingma Tserin, with supporting members, made an attempt on the summit, but they were unable to make much progress on account of their physical condition. The last attempt was planned for the 28th, which fortunately proved a very fine day. Matsuo and Mingma, after ascending the ice-wall, reached a rock peak at 6,200 metres and pitched a tent on the rock ledge. This was Camp V. After spending the night at Camp V. Matsuo and Mingma spent two hours preparing breakfast and they eventually set off for the summit at 8 a.m. The weather had deteriorated somewhat and it was cloudy. After climbing some ice and rock pinnacles, they reached the final ridge which proved to be a real knife-edge covered with bad snow. Five hours after leaving Camp V they conquered the summit of Mt. Numbur. The summit itself was so small that only one person could stand on it. From the summit the news was transmitted by portable radio to the rest of the party at Camp IV. They spent twenty minutes on the summit, during which time photographs were taken. The descent was very difficult as the weather deteriorated further and it began to snow. They stayed at Camp V for the night and reached Camp IV on the 30th, when it was still snowing.

In view of the deteriorated weather conditions it was agreed there would be no further attempt on the summit but instead the party would go down. By June 3 the mountaineering party had joined the scientific expedition at Junbesi.