1951 British Mount Everest reconnaissance expedition

The 1951 British Mount Everest reconnaissance expedition ran between 27 August 1951 and 21 November 1951 with Eric Shipton as leader.

The expedition reconnoitred various possible routes for climbing Mount Everest from Nepal concluding that the one via the Khumbu Icefall, Western Cwm and South Col was the only feasible choice. This route was then used by the Swiss in their two expeditions in 1952 followed by the successful ascent by the British in 1953.

After World War II, with Tibet closing its borders and Nepal becoming considerably more open, the reconnaissance of Mount Everest from Nepal had become possible for the first time.

In 1950 a highly informal trek involving Charlie Houston and Bill Tilman reached what was to become Everest Base Camp on the Khumbu Glacier. Although their report about whether the summit could be reached from there was not very encouraging, they thought an attempt might nonetheless be viable.

By 1951 the location of the South Col was well known – it had been seen from the east in Tibet and photographed from the air – but it had never been possible to view its western side. There remained three main aspects of a route to Everest via the Western Cwm where the difficulties were unknown: the Khumbu Icefall, the climb up to the South Col, and the ascent to the final ridge.

The best evidence about the Icefall was from Tilman and Houston, who were the only people to have seen it close up and who considered it difficult but achievable. The Western Cwm had been glimpsed several times, but it was not clear whether its floor was relatively flat or if it sloped up towards the head of the glacier below the South Col. A pronounced slope might make ascending the valley more awkward but it would reduce the height to be climbed at the head of the valley. Regarding the final ridge, the pair had seen a very steep ridge, quite possibly unclimbable, but they realised that appearances might have been deceptive: the ridge observed might have been blocking the view of a true ridge from the South Col to the summit. The 1921 reconnaissance had ascended the Kama valley east of Everest to approach the Kangshung Face. Observing the South Col from that side, they had seen a seemingly easier ridge linking it to the summit.

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