 Openness is a visualization technique used in archaeology to identify and outline archaeological features on digital terrain models, DTM, derived from airborne laser scanning. Openness does not suffer from directional bias like other shading methods, and can clearly distinguish between relief features and their surroundings. It also provides a clear distinction between the highest and lowest points of features, making it an ideal tool for mapping and outlining archaeological features. When compared to Skyview Factor and local relief model visualizations, Openness has been found to be more effective at identifying archaeological features than either method alone. This article was authored by Michael Donius.