Land art or earth art is a form of art which came to prominence in the late 1960s and 1970s primarily concerned with the natural environment. Materials such as rocks, sticks, soil, plants and so on are often used, and the works frequently exist in the open and are left to change and erode under natural conditions. Particularly large works are sometimes known as earthworks. Many of the works were ephemeral in nature and now only exist as photographic documents.

The movement was inspired mostly by modern and minimal movements such as De Stijl, Cubism, Minimalism and the work of Constantin Brancusi and Joseph Beuys. Many of the artist associated with 'Land art' had been involved with Minimalism and Conceptual Art but according to the critic Barbara Rose writing in 'Artforum ' in 1969 had become disillusioned with the commodification and insularity of gallery bound art. The sudden appearance of Land Art in 1968 can be located as a response by a generation of artists mostly in their late twenties to the heightened political activism of the year and the emerging environmental and womens liberation movements.

The movement was 'launched' in October 1968 by the group exhibition 'Earthworks' at the Dwan Gallery in New York. Perhaps the best known artist who worked in this genre was the American Robert Smithson whose 1968 essay "The Sedimentation of the Mind: Earth Projects" provided a critical framework for the movement as a reaction to the disengagement of Modernism from social issues as represented by the critic Clement Greenberg. His best known piece, and probably the most famous piece of all land art, is Spiral Jetty (1970), for which Smithson arranged rock, earth and algae so as to form a long (1500 feet) spiral-shape jetty protruding into Great Salt Lake in Utah. How much of the work, if any, is visible is dependent on the fluctuating water levels. Since its creation, the work has been completely covered, and then uncovered again, by water.

Smithson's Gravel Mirror with Cracks and Dust (1968) is an example of land art existing in a gallery space rather than in the natural environment. It consists of a pile of gravel by the side of a partially mirrored gallery wall. In its simplicity of form and concentration on the materials themselves, this and other pieces of land art have an affinity with minimalism. There is also a relationship to Arte Povera in the use of materials traditionally considered "unartistic" or "worthless".

Land artists have tended to be American, with other prominent artists in this field including Nancy Holt , Walter De Maria , Hans Haake , Alice Aycock , Dennis Oppenheim , Michael Heizer and James Turrell. Turrell began work in 1972 on possibly the largest piece of land art thus far, reshaping the earth surrounding the extinct Roden Creater volcano in Arizona. Perhaps the most prominent non-American land artists are the British Richard Long and Andy Goldsworthy. Some projects by the artist Christo (who is famous for wrapping monuments, buildings and landscapes in fabric) have also been considered land art by some, though the artist himself considers this incorrect, as explained on his web page. Joseph Beuys' concept of 'social sculpture' influenced 'Land art' and his 'Eichen' project of 1972 to plant 1000 Oak trees has many similarities to 'Land art' processes.

Land artists in America relied mostly on wealthy patrons and private foundations to fund their often costly projects. With the sudden economic down turn of the mid 1970s funds from these sources largely dried up. With the death of Smithson in a plane crash in 1973 the movement lost its figurehead and petered out. Turrell continues to work on the Roden Crater project. In most respects 'Land art' has become part of mainstream Public Art.

In 1998 a group of artists started in Amsterdam (The Netherlands) a project called Indoor Land Art Programme - ILAP, and had shows all over Europe.