When the shelter was first constructed, very little digging was required. The cave system had always existed, simply reinforced with steel and concrete. The deeper tunnels were sealed off. If you place your hands against the walls of these dead-end hallways, you might notice that the stone is twice or in some cases even three times as thick as the concrete used in other parts of the shelter. Whatever lies in those old, dank tunnels, it was clear the old folks had no interest in ever seeing it again.















