Trans-Siberian Railway men and ammunition coming from west to east would have to wait in the sidings, whilst troops and injured personnel in a troop train travelling from east to west went along the line. Thus the Japanese were quickly able to advance whilst the Russians were awaiting necessary troops and supplies. After the Russian Revolution of 1917, the railway served as the vital line of communication for the Czechoslovak Legion and the allied armies that landed troops at Vladivostok during the Siberian Intervention of the Russian Civil War. These forces supported the White Russian government of Admiral Alexander Kolchak, based in
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