Trans-Siberian Railway one side of the lake to the other until the completion of the Lake Baikal spur along the southern edge of the lake. With the Amur River Line north of the Chinese border being completed in 1916, there was a continuous railway from Petrograd to Vladivostok that remains to this day the world's longest railway line. Electrification of the line, begun in 1929 and completed in 2002, allowed a doubling of train weights to 6,000 tonnes. There were expectations upon electrification that it would increase rail traffic on the line by 40 percent. The additional Chinese Eastern Railway was constructed
West Siberian taiga Siberian taiga ecoregion, which is colder and more rugged in terrain. The southern edge of the region lies north of the belt of temperate forests and forest-steppe that runs along the Trans-Siberian railway. Because the West Siberian ecoregion is thus outside of the normal agricultural and developed strip of southern Russia, it is sparsely populated, although the city of Yekaterinburg is at the extreme southwest corner of the region. The city of Surgut is the largest city in the interior (with just over 300,000 inhabitants). To the north is the tundra of the Yamal-Gydan tundra ecoregion (covering the Ob River