During the Cold War period of the late 20th century Britain's fear of a nuclear attack from the Eastern Block was very real.

One aspect of the defensive measures taken was a network of over 700 Royal Observer Corps Monitoring Posts built in locations throughout Scotland. In times of heightened alert these posts would have been manned by the trained volunteers of The Royal Observer Corps.

After a nuclear strike their initial purpose was to report back to a Command Centre the direction from which the blast had come, its elevation, and its strength. With this information from several Posts the powers that be would have been able to triangulate the exact point of impact - ground zero. Over the next two weeks the occupants of the Post could have monitored the amount of fallout and radiation present in their immediate area. Two weeks because that was the amount of supplies stored in the Post to sustain its compliment of three observers. Their only protection was to be 15 feet underground in this bunker, and their technical equipment was basic and simple. Venturing outside after a strike was part of their duty, but with no special protective suits.

However, The Royal Observer Corps was stood down in 1991 and these bunkers no longer have a function in this modern era. Either the threat is diminished or the technology different.

___________________________________________________________________________

This particular Monitoring Post is undergoing restoration by (former) Chief Observer Frank Alexander, and is unique of its type in the whole country in that visits by members of the public are possible at all, if you make a booking on the one or two days per year that it's able to open.
___________________________________________________________________________

Links
It all seems a bit remote and incredible now but this Civil Defence effort was taken seriously enough that the Government spent the money required to maintain this effort over several decades. Booklets and films were produced to inform the population how to survive a nuclear attack, some of which have only relatively recently come to light.
Amazing series of Government information films
BBC Script
Protect and Survive
Domestic Nuclear Shelters
Civil Defence