This geometric maze of vaults and cubicles, where floor, wall and ceiling can melt into a seamless, pure white mass and then emerge in a different guise, could have come from the hand of Piranesi. Two dozen workmen circulated slowly in trucks and bulldozers and on foot, each one oblivious to my presence. Even among themselves there was little talk. I had entered a different world in another time; I saw but was not seen. I had no idea where to begin.