Just a few months later, Hermann Buhl made the first ascent of Nanga Parbat (8,125 m), a siege-style expedition culminating in a last 1,300 meters walking alone, being under the influence of drugs: pervitin (based on the stimulant methamphetamine used by soldiers during World War II), padutin and tea from coca leaves. K2 (8,611 m), the second-highest peak in the world, was first scaled in 1954 by Lino Lacedelli and Achille Compagnoni. In 1964, the final eight-thousander to be climbed was Shishapangma (8,013 m), the lowest of all the 8,000 metre peaks.