reland once had thousands of fortifications like this irregularly shaped stone-ring fort, a farmstead dating from the early Christian period; this is one of the better-preserved examples. During the age of the Viking invasions, it likely provided protection for the local population. Its walls, partially rebuilt in the mid-1920s, measure 2.7m (9 feet) to 3.6m (12 feet) thick. The souterrain (underground stone tunnel) is T-shaped and was likely used in ancient times for cold storage.