In 1996, Joseph Sweet, then 19, and acquaintance Darren F. Blanchard got lost in a system of caves beneath the Veterans Memorial Riverwalk in Watertown, New York.
The men spent two days underground. When the batteries in their flashlight died, they burned some of their cash for light and warmth.
When firefighters finally rescued them, the men were crawling in the wrong direction and showing early signs of hypothermia.
"It is really cool. It’s an incredible story," veteran caver Joseph J. Giunta told the Watertown Daily Times. "They were very lucky, very fortunate to be alive."
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Sweet left his wallet behind in the caves.
According to the Watertown Daily Times, a group of six spelunkers from Western New York found Sweet's dingy black wallet during an exploration of the caves on Saturday.
They were the first people allowed inside the caves since the rescue 16 years ago. Sweet's wallet was right where he left it, not far from the entrance.
Inside it were old bills, library cards, a learner's permit and some salt-damaged coins.
Giunta said that Sweet, who couldn't be reached for comment, was surprised to hear about his wallet.