1) Archaeological feature 
Petroforms, also known as boulder outlines or boulder mosaics, are human-made shapes and patterns made by lining up large rocks on the open ground, often on quite level areas. Petroforms in North America were originally made by Indigenous Peoples, who used various terms to describe them. Petroforms can also include a rock cairn or inukshuk, an upr...
a representational figure laid out on the ground with stones or boulders