My friends took me on a tour of their building development of houses and apartments, in Turkey (nowhere near the usual tourist traps btw). 

As we neared the end of the tour I spotted a huge rectangular hole in the ground and I asked if it was to be a swimming pool.  "No", they said . Hmmmm . . .  I asked if it was some kind of reinforced place of safety in case of earthquake  (duh . . .  underground? You idiot tourist PT).  No, this was not it either.  I asked was it a "bolt hole" in case of nuclear attack?  They said "sort of".

Can anyone clarify?  It seems it is compulsory for developers to provide  these on new sites and my friends said the one where they live is under the children´s play area.

It reminded me of the nuclear bunkers built all around the UK in recent years . . . we had one in our town . . . for "important" people only of course . . . It´s recently been transformed into an "Arts" venue.

My question is:  Has anyone any more details about what I saw in Turkey?

Thanks in advance.