Lunar formations typically described as mare ridges are formally labelled as "DORSUM" whereas networks of such ridges are referred to as "DORSA". Listed below are all forty dorsa typically associated with the visible side of the lunar surface. Each thumbnail image is accompanied by the selenographic coordinates as well as the physical size of the dorsum/dorsa of interest. Clicking on any of the thumbnail images will allow the user to see the same feature in a larger format and which also includes imaging details.