Here and there they spot people moving in and out of the ruins, most of whom appear to be carrying out stones to handcarts, wagons, and other transportation methods. Those vehicles then trundle back towards the built-up section of town with their heavy loads, carrying pre-shaped to form the foundations of the next set of structures to be built.
As they meander back and forth through the structures, it's Ebony who begin to feel like something is catching at the edge of her eye. It takes her several tries and much looking around, but in the end she realizes what her hindbrain has been trying to tell her - one of the structures has people going into it, rather than carrying things out, and while they are loading up a cart with stone, occasionally goods that don't look mining related are heading down into the ruined structure along with the people.
There also seems to be a constant group of folks moving around, chatting, and drinking on the surface near the site, although the numbers and positions are always rotating about.
