World War II ended nearly seven decades ago, but it is not fully behind us. Thousands of tons of munitions lie beneath Germany's soil, unexploded and undiscovered.

In Brandenburg (the state surrounding Berlin) alone, construction workers, bomb locator squads, and others find an average of 631 tons of unexploded munitions per year. Nationwide, the figure reaches 2,000 tons annually. According to Spiegel Online, "Barely a week goes by without a city street or motorway being cordoned off or even evacuated in Germany due to an unexploded bomb being discovered."

And many more remain. Estimates put the total load of unexploded munitions at somewhere between five and 15 percent of the total dropped, or between 95,000 tons and 285,000 tons. “We’ll have enough work to keep us busy for the next 100 to 120 years,” the proprietor of a bomb disposal outfit told The New York Times in 2006.

To make matters more complicated, the work of defusing and disposal is becoming more dangerous and difficult as the bombs degrade. "In the last few years we’ve found that the detonators we take out of such bombs are increasingly brittle," Hans-Jürgen Weise told Spiegel Online in 2008. "Recently we’ve had three extracted detonators go off with a pissssh sound while they were being transported away, all it took was a bit of vibration. One day such bombs will be so sensitive that no one will be able to handle them. We may have to stop defusing them as soon as next year."