30Located in southern Poland, the Wieliczka salt mines had been operating for at least seven hundred years. The deepest of the nine working levels is three hundred and fifty yards underground and the mine’s tunnels, shafts and gangways run for more than ninety miles. A good maze in which to hide the plutonium. Buried deep beneath the earth, the radioactivity was undetectable. But what made the location ideal for Yurlova’s purposes was the diverse and frenetic activity at Wieliczka. Salt was extracted twenty-four hours a day and the vast subterranean labyrinth was a major tourist attraction. Its underground galleries contained chapels hewn from the salt, a museum of old mining equipment and a sanatorium for asthma sufferers. During daylight hours, the upper levels were overrun by visitors,
