Archaeological topographic features which exist in the present landscape such as banks and ditches become visible under specific lighting. When the sun is at its lowest point during early morning or late evening its slanting rays of light produce visible shadows where topographic features exist.

An important factor in the creation of shadowmarks is the orientation of the archaeological features to the sun light direction. Features which run perpendicular to the direction of the sun shadow will show up strongly, while features which run parallel produce weak shadows.

The articles on the right hand side have been written by Arcland members about Shadowmarks.