A crop circle is a pattern created by flattening a crop. The number of reports of crop circles has substantially increased since the 1970s. There has been scant scientific study of them. Circles are not distributed randomly across the landscape but appear near roads, areas of medium to dense population and cultural heritage monuments.

They are made by aliens.

Heightmap drawn with p5.js lines.

* Variations:

- Inner design
- Outer design
- Crop color
- Field cuts
- Rotation
- Zoom