Kirov Railway

The line is of vital military importance because Murmansk is an ice-free port accessible via the Barents Sea: The [...] limiting factor in Russian overseas supply [in World War I] was not ocean shipping.

The primary Russian port, Arkhangel'sk, was served by a single narrow gauge line, which resulted in tremendous backlogs of stores.

[...] The Allies desperately wanted to avoid the White Sea closure by using the warm water ports of the western Murman Coast or Norway.

[...] More promising was the effort to build a seven hundred-mile railway from the ice-free Kola Inlet to the northern terminus of the Russian rail system.

[1] The northern part of the line, between Petrozavodsk and Kola, was built in 1915–1917: due to a lack of workers the Tsarist authorities deployed more than 40,000 German and Austrian prisoners of war to the construction.

Railway between Murmansk on the Arctic Ocean and Saint Petersburg on the Baltic Sea