 In 1923 – 1925 , Lissitzky proposed and developed the idea of horizontal skyscrapers ( Wolkenbügel , " cloud @-@ irons " ) . A series of eight such structures was intended to mark the major intersections of the Boulevard Ring in Moscow . Each Wolkenbügel was a flat three @-@ story , 180 @-@ meter @-@ wide L @-@ shaped slab raised 50 meters above street level . It rested on three pylons ( 10 × 16 × 50 meters each ) , placed on three different street corners . One pylon extended underground , doubling as the staircase into a proposed subway station ; two others provided shelter for ground @-@ level tram stations . 
