I first visited Dia in April 2014. When I came across these installations/displays I initially thought that they were unfinished i.e. that someone was in the process of building an installation. My tastes in art have evolved a lot since then but I still have problems understanding why a pile of broken glass, a pile of sand, a pile of cement and a couple of mirrors are important art. Clearly I still have a way to go. Having said that I do rather like some of his large scale exterior works such as Spiral Jetty and Broken Circle/Spiral Hill.
Wikipedia describes Robert Smithson as follows:
Robert Smithson (January 2, 1938 – July 20, 1973) was an American artist known for sculpture and land art who often used drawing and photography in relation to the spatial arts. His work has been internationally exhibited in galleries and museums and is held in public collections. He was one of the founders of the land art movement whose best known work is the Spiral Jetty (1970).
For (lots) more information see here.
Taken with a Sony A7IV and Samyang 45mm f1.8