"Towards the Development of a Cinema Cavern or the Movie Goer as Spelunker" by Robert Smithson

Smithson imagined making a cinema cavern, with holes drilled through the rock for light, a screen of stone, and a film on endless loop showing how the space came to be. It was never built.

He wrote:

"What I would like to do is build a cinema in a cave or an abandoned mine, and film the process of its construction. That film would be the only film shown in the cave. The projection booth would be made out of crude timbers, the screen carved out of a rock wall and painted white, the seats could be boulders. It would be a truly “underground” cinema."