We still have them in Denmark too, I can see two from my apartment. For a long time, and possibly even today. You were required to build bunkers if you build an apartment building. Sometimes that was done by building the basement in such a way that it would hold storage units that could easily be converted into bunkers. Other times it meant building actual bunkers near the apartment complex.
A lot of the cold-war stuff was rather secret and simply build into the design of public buildings.
My school (from age 6-14, not sure what that’s called in English) had really wide hallways, wide doors, wide elevatory and a huge basement full of stuff that no one outside of the school administration really knew what was. Turns out my school had been designed and build to be converted into a hospital in the case of nuclear war.
Later when I attended the next step in my education, my gymnasium had a water leak. To everyone’s surprise the city closed the entire school for a week and brought in specialists to fix it even though it would typically be up to the local administration to do so. 25 years later we learned that the command center bunker for our region was located under the school.
My story might sound special, it’s not. Almost every public building from that period had a secondary cold-war purpose, but the extend of it has only recently been revealed. It really impresses me, just how prepared our society was, and that my generation never really noticed. Maybe our parents did but mine have never shared much about their cold-war experiences.
Ironically the secrecy didn’t actually work. Recently when Russia opened their soviet archives, it was revealed that they knew every location of every command centre bunker we had, or at least admitted to having.
If Russia knew the location of every command center bunker with less than 100% certainty, then it did work. If instead of the actual command center they knew the location of the 10 potential alternate locations, then they would need to spend 10 nukes instead of 1 (pretty much any concrete bunker is able to withstand anything but a direct hit from a megaton-size nuclear bomb). That complicates a lot the nuclear calculus, even when you have thousands of warheads. In the end, this may have been a small factor in the fact WW3 never happened.
Virtually all nukes nowadays are thermonuclear bombs. If your question is how many bombs have a yield at or above 1 MT TNT, and how many below, then the majority of the current warheads is below. More precisely, currently maybe 90% of the US warheads have a yield between 100 and 455 kT TNT. The largest active warhead in the US inventory has 1.2 MT TNT yield. A rule of thumb is that the more advanced a nuclear program is, the lower the yield of their nukes, the reason being that the a more precise missile can destroy an ICBM silo with a lower yield.
Nuclear bombs (both fission and fusion) direct energy symmetrically in all directions. So any bomb detonated at or above ground level will direct half of its energy towards space. The other half eventually produces damage on the ground, but there are 2 models: surface burst, and air burst. The air burst produces a shock wave that hits the ground and is reflected, and then interferes constructively with the front of the wave that comes at an angle. Generally strikes are designed to maximize the effect of this constructive interference, this was the case with Hiroshima and Nagasaki. However, even this "doubled up" shock wave front is not really that destructive, so any half backed blast resistant shelter can survive it (it doesn't even need to be a concrete bunker, a well designed dug-out shelter will still do it). A surface burst will vaporize a semi-sphere of ground, and no bunker will survive, including even a missile silo, but then the blast effects will be much more localized while the radioactive fall-out will be increased maybe one thousand fold.
Those are air-raid shelters, like we have in Sweden, right?
In Sweden every new building with more than so many occupants had to have a 'skyddsrum'. Local government also had skyddsrums they could manage the civil response to emergencies i.e. attack from.
This is all quite separate from the military bunkers.
And all this isn't quite like these pillboxes that are littering the Albanian countryside.
One country that did build lots of pillboxes after WW2 is Switzerland. If you visit, locals enjoy pointing out various buildings that look like normal mountain chalets but actually have several-meter-thick ground-floors with gun emplacements hidden inside.
https://en.wikipedia.org/wiki/National_Redoubt_(Switzerland)
A lot of the cold-war stuff was rather secret and simply build into the design of public buildings.
My school (from age 6-14, not sure what that’s called in English) had really wide hallways, wide doors, wide elevatory and a huge basement full of stuff that no one outside of the school administration really knew what was. Turns out my school had been designed and build to be converted into a hospital in the case of nuclear war.
Later when I attended the next step in my education, my gymnasium had a water leak. To everyone’s surprise the city closed the entire school for a week and brought in specialists to fix it even though it would typically be up to the local administration to do so. 25 years later we learned that the command center bunker for our region was located under the school.
My story might sound special, it’s not. Almost every public building from that period had a secondary cold-war purpose, but the extend of it has only recently been revealed. It really impresses me, just how prepared our society was, and that my generation never really noticed. Maybe our parents did but mine have never shared much about their cold-war experiences.
Ironically the secrecy didn’t actually work. Recently when Russia opened their soviet archives, it was revealed that they knew every location of every command centre bunker we had, or at least admitted to having.