I was reading an article that was linked on another site I frequent (http://www.archdaily.com/395363/india-s-forgotten-stepwells) on 'India's forgotten stepwells', which are basically elaborate wells with stairs to go down to the water level, sometimes 10m or so below surface (maybe more, looking at the pictures). Some of these are whole temples underground, very impressive-looking.

So I was wondering how one would go about building such a thing, or rather how they would have went about it 1000 years ago. Would you just dig a very big, deep hole, build a structure inside, then fill the sides (can't imagine this)? Is there a way to start at the surface, then work yourself down, basically building layers *under* existing ones?

Similarly, how does/did one go about a brick well? Dig a deep hole, hope it doesn't collapse on top of you, start with brick once you hit the bottom during dry season? Or is there a way to work yourself down there? And does it make a difference nowadays; I mean are there new methods now with modern materials that let you do things they couldn't do 1000, 500 or 100 years ago?

Even just a link to what must be mining engineering 101 is much appreciated :)