>>If Nuclear WWIII happens, this might be where humans survive.
If WWIII happens, there will be plenty of places people will survive. But in dramatically reduced numbers as, firstly, the people living in major population centers would have been killed en masse, and secondly, as a consequence of the first, global supply chains break down and food and other necessities become extremely scarce.
Technology would see massive regression and an extended dark ages as well, as much of the production base would be destroyed, and the people who predominantly live in large population centers and sustain it would be killed.
I only go into these extremely grim details because I'm seeing too many cavaliar attitudes on social media, and even from some officials and former officials (e.g. former Director of National Intelligence, James Clapper, saying it's "a question of time" until Russia does something to force a NATO response) about a possible military confrontation between the West and Russia.