Caisteal Grugaig is an Iron Age broch standing on a small rocky knoll on a grassy slope. The 'Glenelg Brochs' of Dun Telve and Dun Troddan are a few miles to the south. Caisteal Grugaig should not be confused with the 'semi-broch' known as Dun Grugaig which is also near Glenelg.
The broch has an external diameter of around 16.5 metres and an internal diameter of around 9.6 metres. The broch was built on uneven ground, so the natural floor of the broch has a slope. The entrance passage is on the northeast side and has a massive triangular lintel over the doorway. There is an elongated guard cell on the left side of the entrance passage.
The interior of the broch has two intramural rooms at ground level, one of which is a small, oval cell. The other is a long mural cell, or length of ground gallery, which has a blocked doorway. The sides of an upper room are apparent above the entrance passage. Also inside the broch is a doorway to the mural stair. The five steps of the stair lead up to a long landing which leads to the beginning of a second flight of stairs.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.