Robert Smithson is widely regarded as the pioneer of Earth Art, known for his iconic work "Spiral Jetty" (1970).

Earth Art often involves the use of natural materials such as rocks, soil, sand, and plants as the primary medium.

Michael Heizer's "Double Negative" (1969-1970) involved the excavation of two massive trenches in the Nevada desert, creating a dramatic earthwork.

Walter De Maria's "The Lightning Field" (1977) features 400 stainless steel poles arranged in a grid in the New Mexico desert, attracting lightning strikes.

Robert Smithson's "Spiral Jetty" (1970) is a large-scale earthwork constructed from black basalt rocks in the Great Salt Lake, Utah.

James Turrell's "Roden Crater" (ongoing project) is an Earth Art project in Arizona, where a volcanic crater is being transformed into an observatory and artwork.

Crop circles, often associated with Earth Art, are patterns created by flattening crops in fields, forming intricate designs.

Impermanence is a characteristic of Earth Art, as many projects are designed to change over time due to natural processes or human interaction.

Michael Heizer's "The Cross" (1969) is a large-scale earthwork in the Nevada desert, consisting of two intersecting trenches forming a cross shape.

Nancy Holt's "Sun Tunnels" (1973-1976) consists of four concrete tunnels aligned with the solstices and equinoxes, located in the Great Basin Desert, Utah.

Robert Smithson's "Spiral Jetty" (1970) is a large-scale earthwork constructed from black basalt rocks in the Great Salt Lake, Utah, forming a spiral shape.

Richard Long's "A Line Made by Walking" (1967) involves walking long distances and creating temporary artworks, such as lines or circles, using natural materials found along the way.

Michael Heizer's "Double Negative" (1969-1970) involves the excavation of two massive trenches in the Nevada desert, creating a dramatic earthwork in the shape of a triangle.

Christo and Jeanne-Claude's "The Pont Neuf Wrapped" (1985) involved wrapping the Pont Neuf bridge in Paris with fabric, creating a temporary artwork that transformed the iconic landmark.

Michael Heizer's "Double Negative" (1969-1970) involves the excavation of two massive trenches in the Nevada desert, creating a dramatic earthwork in the shape of a circle.