A geoglyph is a large design or motif (generally longer than 4 metres) produced on the ground and typically formed on easily fragmented rocks or similarly durable elements of the landscape, such as stones, stone fragments, gravel, or earth. A Geoglyph can be classified by the method of manufacture.

A negative geoglyph is formed by removing patinated clasts to expose unpatinated ground in a manner akin to a petroglyph. Alternately, it can be formed by scraping away the desert pavements (pebbles covering the ground) to reveal a negative image on the bedrock below. The best known example of such rock art is the Nazca Lines of Peru.

In contrast, a positive geoglyph is a positive images, which is created by piling up rocks on the ground surface in a manner akin to petroforms, and results in a visible motif or design.