The wheelhouse is a fascinating type of Iron Age house, unique so far to the Outer Hebrides and Shetland. They are roundhouses built of stone, and the interiors are divided up by a number of stone piers, arranged like the spokes of a wheel. The individual chambers thus created around the wall of the house were each roofed with a small corbelled stone dome; only the central, open area over the family hearth needed to be spanned with scarce timber, which would be covered over with turf. This ingenious design allowed the building of houses which were quite monumental inside, but which could be built without the need for conspicuously large resources of timber, in contrast to the brochs.
They were also perfectly adapted for the Hebridean environment - they could be built as subterranean structures in sand or machair coastal areas, with only the well-camouflaged roof projecting above the ground, the small doorway giving little clue to the spacious house within, which might be up to 10 metres in diameter and 6 metres high. They could also be built inside pre-existing broch walls, taking advantage of the strong thick shell, or could be built as free-standing structures, such as on the moorland where it was more difficult to dig down. In those cases, a thick blanket of midden material was built up against the outer walls.
The first wheelhouse to be extensively investigated in Lewis was at Cnip in Uig in 1988 as a rescue excavation, where the main house was preserved under the sand up to roof-top level. The building is still preserved behind the beach, although nothing of it is now visible. (Armit 2007).
In Barra, a less well-preserved wheelhouse of free-standing type was excavated in 1994 at Allt Easdal. In the Uists a number were opened throughout the course the earlier 20th century, Bac Mhic Connain on the tidal island of Vallay (NF 769 762), the Udal (Rubha an Udail, NF 824 783), Sollas (A' Choileag Shlignich, NF802 754), Cleitreabhal, Grimsay (Bagh nam Feadag, NF 867 574), West Gerinish (A' Cheardach Mhor, NF 757 413), Drimore (A' Cheardach Bheag, NF 757 404) and Kilpheder (NF 733 203). More details of these can be found in The Lost Wheelhouses of Uist by Susan Hothersall and Robert Tye, 2000.
More are being unearthed as the 21st century progresses, and a reconstructed wheelhouse can be visited at Taigh Chearsabhagh, Lochmaddy, from about 2009 onwards.