Rule 16.1
Ground under repair
Also searched as: GUR, blue stakes, repair area, no play zone
Any part of the course the Committee defines as ground under repair. If your ball lies in it, or it interferes with your stance or swing, you get free relief.
Even without marking, these count as ground under repair: holes made by the Committee or maintenance staff, for example when laying pipes, and piles of grass cuttings or leaves left to be removed.
Ground under repair is one of the abnormal course conditions. You take relief by dropping within one club-length of the nearest point of complete relief, no nearer the hole.