The Shetland Isles 5
Image by notjamesbond
The Shetland Isles

TV last night

Yes, but whichever way you look at it - they are not medieval. Massive time span if you consider extreme views - 700 BC to 900 AD

Interesting point to debate is when did a wheel house or other structure evolve into a broch. First define your broch I guess. Proto-brochs? ;-)

If you are interested in such questions try my Yahoo group (http://groups.yahoo.com/group/circlesettler/), open to all. Originally meant it to be purely about these, then broadened the remit to settlements in Scotland down all the way to late Viking. Still only one other member !