Operation Began with the Southern Half-Circle
The first section of Moscow’s Circle Line began operating on January 1, 1950, between Park Kultury and Kurskaya. Its six stations included those then called Kaluzhskaya, Serpukhovskaya, Paveletskaya and Taganskaya. A metro historical chronology published in 1985 gives its length as 6.4 kilometers, while a contemporary account from 1954 describes it as approximately 7 kilometers. Passenger service began in 1950 before the complete circle was built.
Existing metro lines mainly ran radially toward central Moscow. Passengers traveling between different directions often had to change trains in the center. The Circle Line linked radial routes farther out and connected railway passenger terminals, allowing cross-city journeys to bypass central transfer stations. Construction proceeded in stages, each completed section adding another group of usable connections.
Underground Curves and Construction Organization
Moscow’s metro construction organization built the Circle Line as a deep-level route. Compared with tunneling along a single radial alignment, its curves, gradients and shields advancing from opposing directions increased surveying demands. Underground surveyors repeatedly checked direction and elevation to ensure that tunnels from separate work faces joined at the intended positions.
Excavation, spoil transport and lining installation together determined progress. Crews combined longitudinal and transverse conveyors with rock-loading machinery. On the second section, seven-ton electric locomotives hauled twenty small mine cars instead of the earlier nine-car formations. Mechanical tightening equipment introduced in 1950 reduced the manual work of securing bolts between cast-iron lining segments. Engineers sealed segment joints with cement that expanded while hardening, reducing groundwater leakage and the consumption of nonferrous metals required by earlier caulking methods.
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The Second Section to Belorusskaya
On January 30, 1952, the second section opened from Kurskaya through Komsomolskaya, Botanichesky Sad and Novoslobodskaya to Belorusskaya, a distance of approximately 7 kilometers. Extending northeast and north from the southern section, it linked the Kursky and Belorussky railway terminals and served passengers from several terminals around Komsomolskaya Square.
This stage required more than finished tunnels: escalators, cables, and traction and step-down substations had to be installed. The 1954 account records 27 escalators and six traction and step-down substations on the second section. These facilities made continuous passenger movement possible at deep stations; completing the civil works was one part of bringing the line into operation.
Passenger Flow and Space at Komsomolskaya
The Circle Line’s Komsomolskaya station lies beneath a square containing three railway terminals and connects to the radial station opened in 1935. The earlier small entrance between the Leningradsky and Yaroslavsky terminals could not accommodate growing passenger traffic, making new concourses and passages important parts of the project. Engineers at the metro design institute, led by A. I. Semyonov, investigated a column-supported structure for the broader underground space.
Seventy-two metal columns support three vaults, and the central hall is 159 meters long. Workers assembled a tracked excavator underground to speed the removal of earth. Architect Alexey Shchusev and his collaborators designed light-colored vaults and marble columns, with mosaics by Pavel Korin depicting military-history themes. Passenger circulation, load-bearing structure and commemorative decoration were combined within one station.
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Workers at Kievskaya and the Final Tunnel Breakthrough
The final section ran from Belorusskaya through Krasnopresnenskaya and Kievskaya back to Park Kultury. On August 10, 1953, builders completed the Circle Line’s final tunnel breakthrough beneath the Dorogomilovo embankment near the Kievsky railway terminal. Track, equipment and station finishes still had to be completed: connecting the underground route and opening it to passengers were separate stages.
Metro builder Tatyana Fedorova’s memoir describes Kievskaya’s design by E. I. Katonin, G. Golubev, V. Skugarev and artist A. V. Myzin. Marble worker Fyodor Yakovenko, stucco worker Frol Sviridov and mosaic workers undertook specific finishing tasks. Eighteen mosaics presented the shared history of Russians and Ukrainians as promoted by the Soviet Union at the time, giving the station a political commemorative role as well.
The Transfer Network After Completion in 1954
The Krasnaya Presnya depot entered service on March 9, 1954. Builders held a completion gathering at Kievskaya on March 13. The final 5.9 kilometers opened to passengers on March 14, completing the operating circle. The three stages totaled approximately 19.3 kilometers and connected twelve stations.
Under the 1954 layout, the Circle Line already had six interchange stations connecting to radial lines. Passengers could travel around the circumference to change direction and connect railway terminals with the urban metro. Beyond adding track, the circle introduced a transverse route into a network previously dependent on central nodes. Its transport role came from completing the circle and bringing its transfer facilities into operation together.