Brochs are unique to Scotland. There are over 500 of them, the vast majority spread throughout the northern and western Highlands and the islands. Many of these tall circular towers stood alone, but in Orkney they were generally surrounded by sizeable villages. The broch village at Gurness is one of the most impressive. It has also been archaeologically excavated, thus providing a more vivid impression of life in the Scottish Iron Age than other comparable sites.