Tatlin's Tower

The tower's main form was a twin helix which spiraled up to 400 m (1,300 feet) in height,[3] around which visitors would be transported with the aid of various mechanical devices.

At the base of the structure was a cube which was designed as a venue for lectures, conferences and legislative meetings, and this would complete a rotation in the span of one year.

Further up would be a cylinder, which was to house an information centre, issuing news bulletins and manifestos via telegraph, radio and loudspeaker, and would complete a rotation once a day.

There were also plans to install a gigantic open-air screen on the cylinder, and a further projector which would be able to cast messages across the clouds on any overcast day.

"[3] There are models of Tatlinʼs Tower at the Moderna Museet in Stockholm, Sweden, at Tretyakov Gallery in Moscow, and at Musée National d'Art Moderne at the Centre Georges Pompidou in Paris.

Model of Tatlin's Tower in the courtyard of the Royal Academy, London.