Only a few buildings on the whole site rose to more than a single story aboveground. The most prominent was the head frame: a term from the mining industry referring to the aboveground machinery that bestrode a mine shaft. It was maybe ten meters high and consisted largely of open steel framing through which large reels of cable, motors, and other lifting-and-hoisting sorts of gear were visible. Pipes and cables converged on it from other parts of the complex and plunged down into the shaft.