International art form that developed particularly from the late 1960s and early 1970s. It was part of a revolt against painting and sculpture and the anti-formalist current of the late 1960s that included conceptual art and Arte Povera. A number of mainly British and North American artists turned their attention to working directly with nature, notably Christo and Jeanne-Claude, Walter De Maria, Michael Heizer, Dennis Oppenheim, Robert Smithson, and Richard Long. They created immense sculptures on the same scale as landscape itself, or exhibited written and photographic accounts of their excursions. With few exceptions, their works (also known as earthworks) are almost inaccessible, situated far from human settlements in deserts or abandoned areas. Their lifespan was brief: little by little they were destroyed by the elements and often by erosion, so that for posterity they exist only in the form of preparatory drawings, photographs, or films. The works themselves were seen by only a small number of people and sometimes by only the artist.