In reply to Matt Podd:
Hi Matt,
I've attached a link of a photo of the current exclusion zone, gives you an idea of how you can work around the zone keeping West, the fence at the top of the zone that's South of the Great Rhos trig I used this fence and followed it East to an old gate at the far end and yomped over to Great Rhos, the rest of the route to the other hills Black Mixen and Bache Hill was pretty easy going whilst keeping out of the Zone.
I've never seen anyone up there in an official capacity before. As for safety, probably best to just keep out of the zone. I suppose you could be a rebel and cross the Zone but if you loose a foot in the process that would be a real bummer indeed !
Have a good walk
http://www.herefordshireramblers.org.uk/Great%20Rhos%20M.jpg
L