Sound of Moscow Metrovagonmash 81-717/81-714 departing Soviet Union train - Moscow Metro Branded

81-717/714 is a metro car designed in the Soviet Union in the mid-1970s. The cars were made from 1976 to 2010 by Metrovagonmash and the I. E. Yegorov Vagonmash factories of Mytishchi and Saint Petersburg, respectively. Production is still ongoing for specific models and/or modernizations. The name 81-717 and 81-714 come from the Soviet electric rail vehicle numbering system, where the 81-717 cars are the control cars and the 81-714 are the trailer cars. Unlike the previous metro sets made in the Soviet Union, they never received a lettered classification, thus, they have been known as the 81-series or the “Number Trains“ (Номерной Поезд). The “number trains“, as they are known colloquially among railfans and some commuters, feature restyled front ends, stronger electric traction motors, complex and wider usage of various electronic devices, and are more advanced than their predecessors, the E-series, with the biggest difference being lack of control desks at every end of each car (despite all cars being motorized, though). They were first deployed in Moscow and Prague in 1978, and have since then seen widespread usage in the former USSR and in Warsaw, Prague, Budapest and Sofia in European Union.