The first ascent of <a href="https://en.wikipedia.org/wiki/Mount_Everest" id="mwAR8" rel="mw:WikiLink" title="Mount Everest">Mount Everest</a> without supplemental oxygen, by <a href="https://en.wikipedia.org/wiki/Reinhold_Messner" id="mwASA" rel="mw:WikiLink" title="Reinhold Messner">Reinhold Messner</a> and <a href="https://en.wikipedia.org/wiki/Peter_Habeler" id="mwASE" rel="mw:WikiLink" title="Peter Habeler">Peter Habeler</a>.