Sar River through Rois Nature · Rois, Sar, A Coruña Image of Rois, not of the place itself. The Sar marks the southern boundary of the municipality and its lowest point, at barely six metres above sea level; for centuries its course turned the mills that still dot the municipality's riverbanks. Photo: Sorruno (CC BY-SA 4.0) What to see and do in Rois