was a Japanese alpinist. His achievements include the winter solo ascent of the Great North Faces of the Alps or North Face Trilogy (Matterhorn in 1977, Eiger in 1978, Grandes Jorasses in 1979) and the world's first winter solo ascent of the South Face of Aconcagua in 1981. He died in 1991 in an avalanche while ascending the Ultar Ⅱ South east face.