broch

A broch is a type of Iron Age drystone structure found primarily in Scotland. These towers, typically circular or oval in plan, were built from roughly the 2nd century BCE to the early centuries CE and rise above the surrounding landscape as substantial stone monuments. Brochs are most common in the north and west of Scotland, especially Orkney, Shetland, and the northern mainland, though a number of examples appear in the inner islands and western coastal regions. They are usually preserved only as walls and interior features, with surrounding settlements or enclosures found at many sites.

Construction and design features are distinctive. A broch consists of a thick outer wall that encloses a hollow interior; many survive as a double-skinned wall with a continuous air-space between the skins. The wall often contains galleries, small chambers, and passages built into its thickness, functioning as storerooms or living spaces. Access to the upper floors is typically by a stair passage within the wall, sometimes accompanied by a guard chamber at the entrance. Entrances are narrow and strategically placed, reflecting a degree of defensive planning. Roofs were originally timber or thatch.

Function and significance remain topics of discussion among archaeologists. Brochs are thought to have served as defended dwellings for families or households of status, as well as possible community stores or refuges. Notable examples include Mousa Broch in Shetland, the Broch of Gurness in Orkney, and Dun Carloway on Lewis. Today they are important archaeological monuments that illuminate Iron Age life, technology, and regional variation in northern Scotland.