Sven Hedin was a Swedish geographer, topographer, explorer, photographer, travel writer, and illustrator of his own works. During four expeditions to Central Asia, he discovered the Transhimalaya (once named the Hedin Range in his honor) and the sources of the Brahmaputra, Indus and Sutlej Rivers, Lake Lop Nur, and the remains of cities, grave sites and the Great Wall of China in the deserts of the Tarim Basin. In his book Från Pol till Pol, Hedin describes a journey through Asia and Europe between the late 1880s and early 1900s. While traveling, Hedin visited Constantinople (Istanbul), oil-rich Azerbaijan in times of the Nobel Brothers, Teheran, Mesopotamia (Iraq), lands of the Kyrgyz people, India, China, Asiatic Russia and Japan.