One railway line is still the longest in the world, at 5,772 miles

Built between 1891 and 1916 under a reluctant Tsarist government, the Trans-Siberian Railway links Moscow to Russia's Pacific coast across eight time zones, through terrain that included permafrost, Lake Baikal's cliffs, and a labour force that drew on convicts and soldiers. It remains the longest single railway line on Earth. Its completion let Russia move troops and settlers to its Far East far faster than by horse or river, reshaping the region's politics for a century.

— Steven G. Marks, Road to Power: The Trans-Siberian Railroad and the Colonization of Asian Russia, 1850-1917 — 1991
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