Geography of the Soviet Union:
Lake Baikal

Lake Baikal Shoreline
Lake Baikal Shoreline

Lake Baikal, located in southern (and eastern) Siberia near the city of Irkutsk, is the largest freshwater lake in the world. Very little was known about the lake until the Russian government undertook the construction of the Trans-Siberian Railway in the 1890s, and voila, the government found out that there was this big lake right in the middle of the projected route for the railroad. The lake could not be moved, so they had to build a huge loop around the lake that needed hundreds of bridges and tunnels, which drove up the cost of the railway considerably--in the winter when the lake froze, they rebuilt the railway right across the lake to save time on the trip to Vladivostok. The building of the railway required further, detailed exploration of the lake, and the Russians discovered numerous interesting aspects of Baikal.

Some facts about Lake Baikal:

So, what makes Lake Baikal so unique, a UNESCO world heritage site, besides its deep, clear water?

Lake Baikal lies in a rift valley, a gorge where the crust of the earth is pulling apart. The section of Asia, to the northwest of the lake, is pulling away from the part of Asia to the southeast at a rate of about two centimeters (three-quarters of an inch) a year. In geological terms, the rift is still young and seismically active. There are earthquakes in the region every few years.

Lake Baikal Blue Bar lake Baikal
Lake Baikal from the Air Source is https://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=3664
To the west of Lake Baikal, Russia,
smoke from scores of fires is streaming northwestward in this true-color MODIS image from May 15, 2002.
Blue Bar

The Lake Baikal Environment

In general, Baikal remains one of the cleanest fresh water ecosystems in the world, but environmentalists are concerned over the continuing impact of the Baikal pulp-and-paper plant and the inflow of contaminated water from the Selenga River. In 1966, in the small city of Baikalsk on the southern shore of the lake, a pulp and paper mill was opened. The plant is a known contaminant of the lake with its effluent and maybe also a source of dioxin contamination in the lake. There have been some recent anti-pollution efforts taken by the Russian government. In a clear environmental victory, President Vladimir Putin has called for a new Siberian oil pipeline to be re-routed far to the north, outside the lake's watershed instead of less than a mile from the lake.
PS. The Trans-Siberian Railroad skirts around the lake's southern shores.

Source is http://www.savebaikal.org/img/selenga.jpg
Baikal Pulp and Paper Mill on the lake's shoreline