Think you're extreme? 12,000 years ago Ice Age Humans lived and worked at an altitude of almost 15,000 feet, high in the Peruvian Andes.
The sites in the Pucuncho Basin, located in the Southern Peruvian Andes, are the highest-altitude Pleistocene archaeological sites found to-date. The primary site, Cuncaicha is a rock shelter at 4,480 meters above sea level, with a stone-tool workshop below it. There is also a Pucuncho workshop site where stone tools were made at 4,355 meters above sea level.