4. How to use the basement? The advantages

4.1 Safety

One of the primary roles of the subsoil is to protect people and property from extreme weather, war, looters and malicious intent, thanks to natural, mined or specially dug cavities. Buried treasure is an archetype in every age (and is even practised by some animals). From the personal or family underground cache to the underground refuge for the whole village, all kinds of intermediaries have existed and continue to exist (Banque de France bullion room, ministry bunkers, strike force, etc.). During the Second World War, underground fortifications on the Franco-German border ("Maginot" and "Siegfried" lines) hid guns, troops and logistics, extending the trenches of the previous war (which had no shortage of better-protected annex casemates). Germany had buried several underground...