He was appointed professor of geology at the University of Bonn beginning in 1875, but being fully occupied with his work in China he did not take up professorial duties until 1879. He became professor of geography at the University of Leipzig in 1883, and professor of geography at the Friedrich Wilhelm University of Berlin in 1886. He occupied the latter position until his death. His lectures attracted numerous students who subsequently became eminent in geographical work, and in order to keep in touch with them he established his weekly geographical “colloquium.” Among his most famous students was Sven Hedin, the Swedish explorer. He served as president of the German Geographical Society for many years and founded the Berlin Hydrographical Institute.