The Swiss mounted two attempts on Everest, pre and post-monsoon in 1952. The march-in was from Kathmamdu and they established the route slightly south of Jiri which became the standard route for over 20 years (see 1975 expedition for a map). The spring attempt was led by Edouard Wyss-Dunant with Tenzing Norgay promoted to sirdar for the first time. At the head of the Western Cwm they avoided the Lhotse glacier by taking a more direct route up a buttress they named l'Éperon des Genevois to a point slightly above the South Col. This line of ascent unfortunately turned out to have no adequate site for an intermediate camp. Raymond Lambert and Tenzing eventually reached a height later estimated to have been about on the southeast ridge. In the autumn, led by Gabrielle Chevalley and with Tenzing as both sirdar and full member of the climbing team, one Sherpa was killed by a falling serac and three others were injured when they themselves fell. The expedition then took Shipton's proposed route to the South Col but made little progress any higher.