Snow and wind delayed them at the South Col for two days. They set out on 28 May with the support of Lowe, Alfred Gregory, and Ang Nyima. The two pitched a tent at on 28 May, while their support group returned down the mountain. On the following morning Hillary discovered that his boots had frozen solid outside the tent. He spent two hours warming them over a stove before he and Tenzing, wearing packs, attempted the final ascent. The final obstacle was the 40-foot (12 m) rock face now called "Hillary Step"; Hillary later wrote: