prolly right, i thought they were digging through mountain rock but maybe it's just dirt, either way slaves do the work so...An obvious guess might be that it takes a machine to bore a hole vertically, but with enough slaves you can dig horizontally by hand. Bedrock don't dig real good, topsoil's much easier...
They have plenty of mountains but I’d imagine most of the have a lot of granite. The ones down south do.
prolly right, i thought they were digging through mountain rock but maybe it's just dirt, either way slaves do the work so...