I am creating a world with roughly medieval levels of technology (It is actually in a Dungeons and Dragons campaign) and the world has just been almost destroyed.
A city has been flattened to the foundations, and the survivors are trying to rebuild. They can find all the common resources they need (There is stone all over the place, tools are easy enough to come by etc) but have to rely entirely on the manpower of the townsfolk that survived (No magic for example). Anything uncommon I probably haven't thought of because I can't even put up flat-pack furniture never-mind build a wall, but they would likely have to acquire that so it would be an obstacle to progress, and useful for me to know
They won't be looking to rebuild a metropolis, just a town / village big enough to be called a worthwhile* settlement. Considerations are probably building a defensive wall, setting farmland, and enough shelter for however many people are in the town (The first place this will apply to has ~250 people).
*Worthwhile can be defined as: buildings that don't fall over in a storm, though they can be part wood and part stone; enough of them to provide shelter for the individuals; some kind of gathering hall (tavern maybe); plus clearing enough land to farm enough produce to sustain them.