Originally there was a large mosaic panel "Stalin on a tribune" located on a prominent wall of the central underground hall. This mosaic was constructed by the director of the Academy of Arts of the Soviet Union, Aleksandr Gerasimov. Stalin's bust was planned to be displayed on a colourful background; however, in 1961, after the 22nd Congress of the Communist Party of the Soviet Union, the panel was covered by a false wall of marble, with a photo of the original panel included in the book dedicated to the line's opening.