In both his book Rawles on Retreats and Relocation and in his survivalist novel, Patriots: A Novel of Survival in the Coming Collapse, Rawles describes in great detail retreat groups "upgrading" brick or other masonry houses with steel reinforced window shutters and doors, excavating anti-vehicular ditches, installing warded gate locks, constructing concertina wire obstacles and fougasses, and setting up listening post/observation posts (LP/OPs.) Rawles is a proponent of including a mantrap foyer at survival retreats, an architectural element that he calls a "crushroom".
The increased inflation rate in the 1960s, the US monetary devaluation, the continued concern over a possible nuclear exchange between the US and the Soviet Union, and perceived increasing vulnerability of urban centers to supply shortages and other systems failures caused a number of primarily conservative and libertarian thinkers to promote individual preparations. Harry Browne began offering seminars on how to survive a monetary collapse in 1967, with Don Stephens (an architect) providing input on how to build and equip a remote survival retreat. He gave a copy of his original Retreater's Bibliography to each seminar participant.
Another concern when you’re lost in the wild is where to procure potable water. Sometimes there will be bubbling streams of crystal clear water rolling down wooded hillsides to fill your water bottle and sometimes you’ll have little more than a stagnant pool standing between you and dehydration. The LifeStraw Personal Water Filter is survival gear that can turn that stagnant pool into a lifesaver.