A broch brɒx is an Iron Age drystone hollow-walled structure found in Scotland. Brochs belong to the classification "complex Atlantic roundhouse" devised by Scottish archaeologists in the 1980s.
Brochs are roundhouse buildings found throughout Atlantic Scotland. The word broch is derived from the Lowland Scots 'brough', meaning fort. In the mid-19th century, Scottish antiquaries called brochs 'burgs', after Old Norse borg, with the same meaning. Brochs are often referred to as duns in the west, and they are the most spectacular of a complex class of buildings found in northern Scotland. There are approximately 571 candidate broch sites throughout the country, according to the Royal Commission on the Ancient and Historical Monuments of Scotland.
The origin of brochs is still subject to ongoing research. While most archaeologists believed 80 years ago that brochs were built by immigrants, there is now little doubt that the hollow-walled broch tower was an invention in what is now Sc