geoglyph

A very large design or image produced on the ground and fully visible only from the air.  Geoglyphs are typically formed of durable elements of the landscape, such as stones, gravel, or earth. The most famous geoglyphs are the Nasca lines in Peru and the horse and human figures cut into hillsides in southern England (e.g., the Uffington White Horse and the Cerne Giant).

Marree Man (a.k.a. Stuart’s Giant). South Australia. Late 20th c. Photo: Phil Turner.