Since 1968, Koblmueller participated in expeditions in the Andes, in the Hindu Kush, in the Karakoram and the Himalayas, and achieved important first ascents. His most important accomplishment was the first ascent of the Southeast Face of Cho Oyu (8201 m/26,906 ft) in 1978 together with Alois Furtner [3]. Koblmueller was considered one of the most successful Austrian expedition mountaineer, and reached five eight-thousanders.