Starting from Tukusha, the climbers Lachenal and Rébuffat headed for an initial exploration of Dhaulagiri's eastern glacier, while Herzog, Terray and Ichac went to the north where they found their 1920s map was seriously defective (see above). Unlike Annapurna, Dhaulagiri is well separated from its neighbouring peaks and it is steep on all sides. They found an unmapped region they called the Hidden Valley but from there they were unable to see the mountain at all. Over the next two weeks small groups examined the southeast and northeast ridges while Terray and Oudot reached a pass (called French Pass) beyond the Hidden Valley but, although they were able to see Dhaulagiri, they decided the north face could not be climbed. They were also able to see across to Annapurna in the distance where there were steep cliffs to the south but the northern profile did not look to be more than 35°.