Researchers working in the Peruvian Andes have found an ice age camp located 14,760 feet (4,500 meters) above sea level. It's so high that the archaeologists were surprised ancient humans could even survive up there.

Photo: Matthew Koehler/Science/AP.

The 12,400 year-old settlement, called the Pucuncho workshop site, is more than 6,560 feet (2,000 meters) higher than the famous Inca archaeological site Machu Picchu, a popular attraction that often induces altitude sickness in tourists. Incredibly, it's just 2,280 feet (880 meters) lower than the Mount Everest base camp in the Himalayas. The camp was found in a cave called the Cuncaicha rock shelter, which is about 14,760 feet (4,500 meters) above sea level. So at 2,950 feet (900 meters) higher than any previously dated contemporary camp, it's the highest Pleistocene site yet identified in the world.

Photo: Kurt Rademaker/Science/AP.

At that height, the air is cold and thin, and the sun easily burns the skin. And in fact, the harsh environment made it difficult for the international research team working there; they had to battle headaches and exhaustion from low oxygen, and cope with freezing temperatures and rugged camping conditions.

Photo: David Reid.

The realization that paleoindians were living at these altitudes a mere 2,000 years after entering South America shows how quickly humans can adapt to extreme conditions. That said, the archaeologists are not claiming that these ancient people were genetically adapted to the conditions.

Photo: David Reid.

"Other people have suggested that people could not and did not live at those elevations prior to genetic adaptations occurring," noted archaeologist Sonia Zarrillo in a CBC article. "What we're showing is either they were genetically adapted to living up there or it didn't matter."

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The archaeologists say it's unlikely the paleoindians lived at the site year round. The rock shelter at the site was big enough to fit about 20 to 30 people. Excavations at the site yielded scrapers and tools used to process animal hides (for making clothing and tents). Evidence indicates that family groups lived at the site for long periods of time, and that they subsisted heavily on meat, especially on llama-like vicunas and guanacos. Clearly, the area featured important resources, making it an attractive habitable settlement during the more pleasant times of year.

More at the CBC. And read the entire study at Science: "Paleoindian settlement of the high-altitude Peruvian Andes".