At the age of seventeen he climbed the Walker Spur in the Grandes Jorasses and one year later he climbed the north face of the Eiger. After a visit to the Saxon Switzerland climbing area in Saxony, Germany in 1973 he recognized the potential of free climbing (free climbing was practised in Saxony since the early 19th century). He started to free climb in his home climbing area, the Frankenjura. In the routes he would now try to ascend while free climbing, he would—in between attempts—paint a red 'X' on the rocks near pitons he did not need as holds or steps. Once he could place a red 'X' on all the pitons and hooks in the route, and was thus able to free climb the entire route, he would paint a red dot at the base of the route. From this comes the English term redpoint, which is derived from the German Rotpunkt, meaning red point. In many ways this was the origin of the free climbing movement that led to the development of sport climbing some years later.