Numbur, Rolwaling Himal. The Himalayan Expedition of Chiba University consisted of six Japanese: Makoto Numata, leader, Kazumoto Suzuki, sub-leader, Kyoji Yoda, Koichiro Shimada, Hiroshi Matsuo, Kodzo Kohama, and one Swiss guest: A. P. Hirsbrunner. We left Kathmandu on April 18 and arrived at Junbesi Base Camp (9000 feet) of the ecological survey on April 29. The mountaineering party left Junbesi and followed the Solu Khola on May 1 and the next day established Base Camp at 13,125 feet. We pitched Camp I (15,000 feet) on May 5, Camp II (15,000 feet) on May 10 in the upper part of the Dudh Kund and Camp III (16,400 feet) on May 12. Here the climbing became more difficult. Camp IV was made at 18,375 feet on May 12, and Camp V at 21,650 feet only on May 28. The wall of blue ice between these last two camps was most difficult to climb. The rainy season had already started and the weather was not good. Hiroshi Matsuo and the Sherpa Mingma Tsering left Camp V early on May 29 and reached the final ridge, which was a steep knife-edge with bad snow. After five hours of difficult climbing, they conquered the summit of Numbur (22,815 feet). The summit was small and only one could stand on the top at a time. The descent was difficult because the snow storm came in. They stayed at Camp V that night and reached Camp IV on May 30 in the snow storm. We had only one chance to climb the summit.
Makoto Numata, Chiba University, Japan