it is not downwind of any envisioned nuclear targets in the United States. Mel Tappan was disappointed by the demographics of southwestern Oregon after the survivalist influx of the late 1970s. "Too many doctors and lawyers" relocated to Oregon, and "not enough plumbers, electricians, or carpenters." Evacuation to a retreat While some survivalists recommend living at a rural retreat year-round, most survivalists cannot afford to do so. Therefore, they rely on keeping a well-stocked retreat, and plan to go there "at the 11th hour", as necessary. They keep a bug-out bag handy, and may have a dedicated bug-out vehicle (BOV). This is a vehicle that the owner keeps prepared in the event of the need for an emergency evacuation. Typically a BOV is equipped with a variation on the bug-out bag that includes additional automotive supplies, clothing, food, and water. Survivalists tend to favor four wheel drive trucks and SUVs due to their greater off-road abilities. Survivalists may opt into maintaining an older vehicle since it more likely lacks critical electronic components that could be damaged by the electromagnetic pulse that accompanies a nuclear explosion. Retreat organization Most survivalist retreats are created by individuals and their families, but larger "group retreats" or "covenant communities" are formed along the lines of an intentional community. Retreat architecture and security Jeff Cooper popularized the concept of hardening retreats against small arms fire. In an article entitled "Notes on Tactical Residential Architecture" in Issue #30 of P.S. Letter (April, 1982), Cooper suggested using the "Vauban Principle", whereby projecting bastion corners would prevent miscreants from being able to approach a retreat's exterior walls in any blind spots. Corners with this simplified implementation of a Vauban Star are now called "Cooper Corners" by James Wesley Rawles, in honor of Jeff Cooper. Depending on the size of the group needing shelter, design elements of traditional European castle architecture, as well as Chinese Fujian Tulou and Mexican walled courtyard houses have been suggested for survival retreats. 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