Trans-Siberian Railway imperial collapse, and before the Red Army took control, the Czechs and Slovaks were able to use their organisation and the resources of the railway to establish a temporary zone of control before eventually continuing onwards towards Vladivostok, from where they emigrated back to Czechoslovakia. During World War II, the Trans-Siberian Railway played an important role in the supply of the powers fighting in Europe. During the first two years of the war the USSR had secretly agreed to a neutrality and non-aggression pact with Germany. While Germany's merchant shipping was interdicted by the Western allies, the Trans-Siberian Railway (along
Trans-Siberian Railway from one side and then exit China and return to Russia on the other side) on this branch, it is still used by several international passenger services between Russia and China. The third primary route is the Trans-Mongolian Railway, which coincides with the Trans-Siberian as far as Ulan-Ude on Lake Baikal's eastern shore. From Ulan-Ude the Trans-Mongolian heads south to Ulaan-Baatar before making its way southeast to Beijing. In 1991, a fourth route running further to the north was finally completed, after more than five decades of sporadic work. Known as the Baikal Amur Mainline (BAM), this recent extension departs