Interesting SY cheers its also surprising how many Lives where saved by the old Anderson Shelters when well dug in and sand bagged. My Mum used to use one when she wasnt at work in the local Ilford film manufacturers when the raids where on.
Ahh - yeah, these were built when nukes still had relatively low yields. Soon enough it became clear that they wouldn't withstand a ground burst from a big nasty ICBM. Therefore they built a huge bunker outside Bath called RAF Corsham where the central Government could run the country from. It's still an active MOD site - although it's been mothballed.
There are other smaller bunkers around the country for regional seats of government (SRHQ's) - preserved ones include Hack Green, Kelvedon Hatch and Anstruther.
Kelvedon is about 3 miles from my home town ,even in the 60's we all new its location (so much for secret bunkers) I think the constant flow of vehicles too and from a woods in the middle of no where was a bit of a give away.