The man, whose name was not released, was swimming near the Coppermine parking area off Old Mine Road in Warren County, parks spokeswoman Kathleen Sandt said.
Multiple calls for a swimmer in distress came in around 3:50 p.m., and patrol rangers located the man's body around 5 minutes later, Sandt said.
The victim's body was recovered from the water 4:25 p.m., officials said.
The water where the victim was swimming is not a designated swimming area, although swimming is not prohibited, Sandt said.
The incident marks the fifth park drowning in the last six weeks.
While the Newark man was being recovered, someone else was being rescued from the water at Kittatinny Point, who was breathing and taken to the hospital, officials said.
Last Sunday, a 30-year-old New Jersey man drowned in the park after going swimming in the same site off Old Mine Road. His body was recovered on the PA side of the park, officials said.
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