One of the most well-known exponents of North American land art, Smithson influenced the subsequent generations of artists also through his research and studies as a critic, centered on the various features of the environment and on the possible ways of intervening on them. In the beginning a painter, influenced primarily by pop art, he subsequently approached the minimalist movement with a type of sculpture that studied reflexes and crystalline structures. In this way, he introduced the concept of entropy, essential in his work, intended as the search for a balance between opposites such as order and chaos, destruction and renovation, non-sites and the possible interventions on context (earthworks). Sites and non-sites will define his work, the first meaning the action of transforming a context, and the latter the photographic documentation of an environment, be it natural or not, with elemental evidence (rocks, glass, earth) to display in galleries. In addition to his more famous earthworks, such as Asphalt Rundown realized in Italy in 1969, Partially Buried Woodshed (1970), the gigantic Spiral Jetty (1970) on Great Salt Lake in Utah, Broken Circle/Spiral Hill (1971), of primary importance were his studies on Central Park in New York and on landscape architecture, which constantly proposed the parallel/comparison between the XIX Century ‘picturesque’ (and the inventions of F. L. Olmsted) and the reality of the degraded physical context, prior to the creation of the park itself and, subsequently, the consequences of its insertion in a continuously evolving urban context.