[mahrain]

Northern Europe had a very similar facility, a large "underground city" in The Netherlands near Maastricht, being used as a command center / information hub in NATO for the airspace. Unfortunately in the construction was a lot of asbestos, and it was completely dismantled. Small tours are given by former employees though! https://en.wikipedia.org/wiki/NORTHAG_War_Headquarters_Canne...

[BoxOfRain]

There's quite a few extensive underground structures scattered around the UK too that were built to defend against Soviet bombers, some of them started life as part of the original Chain Home system from the Second World War and were reactivated as part of the ROTOR programme in the 1950s. Some had a very short life as radar technology quickly improved, leading to many sites being abandoned while some became regional headquarters for dealing with civil emergencies. They're characterised by a specific design of bungalow which conceals a staircase down to a long, sloping corridor into the bunker system below.

A few are preserved today as Cold War museums, but most are sealed off and occasionally become high-value locations for British urbexers on the odd occasion access becomes available. Historically there was a subculture around exploring such places and documenting them for posterity, but YouTube kind of ruined it by making interesting abandoned sites magnets for vandals and attention-seekers which is the last thing you want in those places.

The ROTOR bunkers would take a braver man than me to explore though, they're often burned out, flooded, and full of asbestos with all the interesting 1950s tech long removed. Not to mention they're often located on farmland where the landowners are fed up of said YouTube crowd traipsing around.