NEENAH, Wis. — When Ken Zwick and Carol Hollar-Zwick bought their home in 1999, they knew the backyard contained an underground fallout shelter built during the height of the Cold War.

What they didn’t know — and wouldn’t discover until they ventured into the shelter more than a decade later — was that the previous homeowner stocked the bunker with food and survival supplies in 1960.

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“We assumed it was just this empty space,” Hollar-Zwick said.

When the Zwicks unlocked the heavy, metal hatch, they found watertight Army surplus boxes floating in 5 feet of water that had seeped into the shelter. The boxes’ contents were in pristine condition.

A few boxes bore labels suggesting they might contain explosives, so agents from the federal Bureau of Alcohol, Tobacco, Firearms and Explosives responded to investigate, but nothing dangerous was inside.

“It was Hawaiian Punch,” Hollar-Zwick said. “It was all of what you would expect to find in a 1960s fallout shelter. It was food, clothing, medical supplies, tools, flashlights, batteries — items that you would want to have in a shelter if you planned to live there for two weeks.”

The Zwicks had no use for the food and supplies, so they donated them to the Neenah Historical Society in this city of almost 26,000 about 80 miles northwest of Milwaukee. They resisted the temptation to sample the food.

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