4.4 Radiocarbon dating of the Iceman Ötzi with accelerator mass spectrometry

On 19 September 1991 an extraordinary archaeological discovery was made at a high-altitude mountain pass (Tisenjoch, 3210 m) of the Ötztal Alps near the Austrian-Italian border. Two mountain hikers from Nürnberg, Erika and Helmut Simon, after having scaled the Finail Peak (3516 m) that day were on their way back to the Similaun mountain hut (3019 m) located at the lowest part of a mountain ridge connecting the Finail Peak with the Similaun (3607). This ridge forms the border between Austria (to the north) and Italy (to the south). As the hikers approached a shallow ice-filled depression along the ridge, they were startled by seeing the body of a man sticking half-way out from the ice. Unusual climatic conditions in the summer of 1991 (including dust from Sahara resulting in enhanced melting of snow) had partly freed the body from his icy grave. The Iceman was later nicknamed “Ötzi”, after the mountain range where he was found. Two days after the first discovery, Hans Kammerlander and Reinhold Messner, two famous mountain climbers from South Tyrol happened to arrive at the site, and the photo of figure 1 shows them watching the Iceman. Messner made a first guess at the age of the man and thought he might have died some 500 years ago. Another two days later (on 23 September 1991) the body was recovered from the ice by Rainer Henn from the Institute of Forensic Medicine at the University of Innsbruck, and was flown to his institute by helicopter. Next day, when Konrad Spindler from the Institute of Preand Protohistory of the University of Innsbruck saw the unusual pieces of equipment found together with the body (in particluar an ax with a bronze-like blade), he estimated a very old age (~4000 years) of the find. This immediately created great excitement for both scientists and the public, resulting in many “colorful” events in the ensuing weeks.