Rona, a remote Scottish island, is said to have been the residence of Saint Ronan, Abbot of Kingarth in Bute (died 737). A tiny early Christian oratory which may be as early as this date, built of unmortared stone, survives virtually complete on the island. The site of one of the most complete Early Celtic religious complexes in Scotland. North Rona was abandoned after the Viking raids, but resettled by a secular community in the 12th or 13th century. Disasters, such as the drowning of the island's entire male population, and starvation brought about by a plague of rats, resulted in only intermittent occupation during subsequent centuries; the last resident, Donald Macleod, left in 1844 . North Rona is now a National Nature Reserve with Sula Sgeir.
Sited on a terrace within a thick-walled, oval burial enclosure, Teampall Rònain was probably a hermitage offshoot from the church at Europie in Lewis. It is two-chambered, the almost subterranean corbelled eastern cell being the late 7th/early 8th century `oratory' of St. Ronan, beautifully constructed with inward-leaning walls bridged over with stone slabs, traces of lime mortar still clinging to the sides. On the west wall, a door with slit window above leads into the 12 th-century chapel, its west gable still standing to six or seven ft. A stone-paved doorway was uncovered by Dr. Frank Fraser Darling on the south wall during his repair works here in 1938. He also excavated the east end of the earlier structure, unearthing the base of a stone altar and wall niche. Numerous Early Christian and medieval incised cross slabs lie on the site.References:
Roman Walls of Lugo are an exceptional architectural, archaeological and constructive legacy of Roman engineering, dating from the 3rd and 4th centuries AD. The Walls are built of internal and external stone facings of slate with some granite, with a core filling of a conglomerate of slate slabs and worked stone pieces from Roman buildings, interlocked with lime mortar.
Their total length of 2117 m in the shape of an oblong rectangle occupies an area of 1.68 ha. Their height varies between 8 and 10 m, with a width of 4.2 m, reaching 7 m in some specific points. The walls still contain 85 external towers, 10 gates (five of which are original and five that were opened in modern times), four staircases and two ramps providing access to the walkway along the top of the walls, one of which is internal and the other external. Each tower contained access stairs leading from the intervallum to the wall walk of town wall, of which a total of 21 have been discovered to date.
The defences of Lugo are the most complete and best preserved example of Roman military architecture in the Western Roman Empire.
Despite the renovation work carried out, the walls conserve their original layout and the construction features associated with their defensive purpose, with walls, battlements, towers, fortifications, both modern and original gates and stairways, and a moat.
Since they were built, the walls have defined the layout and growth of the city, which was declared a Historical-Artistic Ensemble in 1973, forming a part of it and becoming an emblematic structure that can be freely accessed to walk along. The local inhabitants and visitors alike have used them as an area for enjoyment and as a part of urban life for centuries.
The fortifications were added to UNESCO"s World Heritage List in late 2000 and are a popular tourist attraction.