– the Sorkonozhka (Centipede) was created. Consisting of an enclosed concrete prism, it featured two supporting rows of pillars for the ceiling. The original design was standardised to the point where stations differed only in the colour of marble on the pillars and the ceramic tiling patterns of the walls. However the method allowed for even further increase in construction methods. A rational combination of using deep-level shield tunnels and a sub-surface station pit allowed for this, and would become the most widely used technique in many ex-USSR metro systems. In 1962 the Kaluzhskaya line was opened, and in 1964 it had its first extension to the new Kaluzhskoye depot where a temporary surface station was opened. Transfer points Originally it was thought that the two radii could exist on their own and terminate at the ring; however, the dynamic passenger inflow immediately made the Metro planners realise the mistake. To correct this, it was decided to link the radii to a diameter and relieve the ring by allowing several transfer points inside the circumference. In 1970 the first extension northwards from Oktyabrskaya took place where the line met up with the Tagansko-Krasnopresnenskaya line at Kitay-gorod, for the first time, a combined cross-platform transfer was opened with both stations built simultaneously. Finally, at the end of 1971, the lines linked up with the central section forming the Kaluzhsko–Rizhskaya line. The two stations that formed the final junction used a new method of mounting hydroisolation, which was made separately and then suspended instead of mounting it piece by piece. This allowed a three-month work to be finished in little more than a week. Extension projects North After the joining of the radii the line became a full transport artery. Several more extension projects were carried out. A northern one opened in 1978 and finally allowed the late Soviet decorative architecture to blossom. At four stations long, it extended past the Russian Botanical Gardens into the new northern districts of Babushkinsky and Medvedkovo. The extension also featured a new depot. Part of the track lies across Yauza River though passengers can not see it as the track bridge is a covered tunnel. South At the same time several projects on the southern radius took place. In 1974 the temporary depot station was closed and the line expanded into Belyayevo. In 1980 Shabolovskaya was opened between Oktyabrskaya and Leninsky Prospekt stations. The original