I'm not quite sure about the names of the Scottish counties, but the area coloured in looks about right. Also I must have passed through Somerset to get to Cornwall and Devon, but I don't think I'd count is as "having visited".
I've visited the counties in yellow.
Which counties have you visited?
made by marnanel
map reproduced from Ordnance Survey map data
by permission of the Ordnance Survey.
© Crown copyright 2001.