12 May 1974,
The Tximist expedition was 320 metres from the Everest Summit. The expedition was financed by the vitorian company Tximist, led by Juan Zelaia, and composed of 16 members. Felipe Uriarte and Angel Alexandre Ros planned to summit the next day, but the storm prevented them. Six years later, it was the history of the expedition that reached the top in 1980.
Source:
Wikipedia – Tximist 1974 expedition.