Survivalists are sometimes thought of as people with a bunker, a secure underground dwelling. This is the definition taken by a book which has been getting the sales, by Bradley Garrett, Bunker: Building for End Times (Scribner, New York, 2020):
https://www.amazon.com/Bunker-Building-Bradley-Garrett-Ph-D/dp/1501188550
It is critiqued by my favourite multiracial survivalist, Canadian Prepper here:
https://www.youtube.com/watch?v=Ow8bZOq02Yw
Having a bunker is not essential to being a off grid extremist nut case, like yours truly. My bunker is the bush. Actually, the bunker is really a metaphor for what has been called a “sustainable autonomous base”:
https://www.amazon.com/Piero-San-Giorgio/dp/1593680147/ref=sr_1_2?dchild=1&keywords=survive+the+economic+collapse&qid=1598166643&s=books&sr=1-2
Most important of all, the bunker is a state of mind, living in a siege mentality, seeing enemies, everywhere, which they are. So, I definitely live in a bunker world, being red and black pilled (there is an article on this at the site). But many are not, living in a world that has passed away. They will be crushed by the wheels of history if they live long enough, to die.