was studied by scientists from a number of countries, including Russia (geologist Alexander Karpinsky, botanist Porfiry Krylov and zoologist Leonid Sabaneyev), the United Kingdom (geologist Sir Roderick Murchison), France (paleontologist Édouard de Verneuil), and Germany (naturalist Alexander von Humboldt, geologist Alexander Keyserling). In 1845, Murchison, who had according to Encyclopædia Britannica "compiled the first geologic map of the Ural in 1841", published The Geology of Russia in Europe and the Ural Mountains with de Verneuil and Keyserling. The first railway across the Urals had been built by 1878 and linked Perm to Yekaterinburg via Chusovoy, Kushva and Nizhny Tagil. In 1890 a railway linked Ufa and Chelyabinsk via Zlatoust. In 1896 this section became a part of the Trans-Siberian Railway. In 1909 yet another railway connecting Perm and Yekaterinburg passed through Kungur by the way of the Siberian Route. It has eventually replaced the Ufa – Chelyabinsk section as the main trunk of the Trans-Siberian railway. The highest peak of the Ural, Mount Narodnaya, (elevation 1,895 m [6,217 ft]) was identified in 1927. During the Soviet industrialization in the 1930s the city of Magnitogorsk was founded in the South-Eastern Ural as a center of iron smelting and steelmaking. During the German invasion of the Soviet Union in 1941–1942, the mountains became a key element in Nazi planning for the territories which they expected to conquer in the USSR. Faced with the threat of having a significant part of the Soviet territories occupied by the enemy, the government evacuated many of the industrial enterprises of European Russia and Ukraine to the eastern foothills of the Ural, considered a safe place out of reach of the German bombers and troops. Three giant tank factories were established at the Uralmash in Sverdlovsk (as Yekaterinburg used to be known), Uralvagonzavod in Nizhny Tagil, and Chelyabinsk Tractor Plant in Chelyabinsk. After the war, in 1947–1948, Chum – Labytnangi railway, built with the forced labor of Gulag inmates, crossed the Polar Ural. Mayak, southeast of Yekaterinburg, was a center of the Soviet nuclear industry and site of the Kyshtym disaster. Geography and topography The Ural Mountains extend about from the Kara Sea to the Kazakh Steppe along the border of Kazakhstan. Vaygach Island and the island of Novaya Zemlya form a further continuation of the chain on the north. Geographically this range marks the northern part of the border between Europe and Asia. Its highest peak