Before anyone builds a structure, the first concern should be about setting a firm foundation. In our town, over a century ago, the community fathers mined coal using the room and pillar method, some 300 feet below the surface. Miners left pillars of coal to support the ceilings, and the rooms extended underground for miles. Later, methods developed to extract the pillars, and wood structures were placed to hold the roof. But the supports didn’t last.Full text here - https://www.tomorrowsworld.org/commentary/infrastructure-and-a-solid-foundation