Four years ago, archeologists made a chilling discovery while examining the excavation site of the former World Trade Center — they found the skeleton of an ancient sailing ship buried 20 feet below the ground’s surface.

With a hose and gloves, they began to dig. They had limited time to remove the ship before construction resumed on an area slated to house vehicle ramps leading to parking beneath the new World Trade Center. (Image source: Lower Manhattan Development Corporation)

With a hose and gloves, they began to dig. They had limited time to remove the ship before construction resumed on an area slated to house vehicle ramps leading to parking beneath the new World Trade Center. (Image source: Lower Manhattan Development Corporation)

After making the ghostly discovery in July 2010, historians offered various theories on how a 30-foot piece of the vessel made its way to lower Manhattan.

No one was, however, able to say with confidence where it came from and the mystery largely endured — at least until today.

With a hose and gloves, they began to dig. They had limited time to remove the ship before construction resumed on an area slated to house vehicle ramps leading to parking beneath the new World Trade Center. (Image source: Lower Manhattan Development Corporation)

With a hose and gloves, they began to dig. They had limited time to remove the ship before construction resumed on an area slated to house vehicle ramps leading to parking beneath the new World Trade Center. (Image source: Lower Manhattan Development Corporation)

Tree ring scientists at Columbia University’s Lamont-Doherty Earth Observatory analyzed the ship’s remains and concluded this month that a forest in the Philadelphia area provided the white oak for the vessel’s frame.

According to their findings, published in the journal Tree Ring Research, the trees were likely cut in 1773 — just years before the American revolution.

Wood sampled from Philadelphia’s Independence Hall matched those of the ship, indicating the two probably came from the same region.

Several ring patterns matched oak timbers found in Philadelphia’s Independence Hall, where the Declaration of Independence and U.S. Constitution were signed. Lamont-Doherty scientist Ed Cook sampled Independence Hall in the late 1980s while amassing his North American Drought Atlas; those records would be crucial in tracing the World Trade Center ship’s timbers to a dense, old-growth forest near Philadelphia. (Image source: Library of Congress)

Several ring patterns matched oak timbers found in Philadelphia’s Independence Hall, where the Declaration of Independence and U.S. Constitution were signed. (Image source: Library of Congress)

Scientists believe that the ship was, thus, built in Philadelphia. It appeared to have been designed to carry Dutch passengers and cargo over shallow waters.

The ship was identified as a Hudson River Sloop, designed by New York’s first European settlers, the Dutch, to carry passengers and cargo in shallow, rocky waters. In the 1970s, folk singer and activist Pete Seeger built a Hudson River Sloop replica named Clearwater, and used it as a platform to lobby for the removal of toxic PCBs and other pollutants from the Hudson. (Image source: Anthony Pepitone)

The ship was identified as a Hudson River Sloop, designed by New York’s first European settlers, the Dutch, to carry passengers and cargo in shallow, rocky waters. (Image source: Anthony Pepitone)

The vessel likely found it’s final resting place on Manhattan’s lower west side, but was buried as the shoreline gradually pushed further west, according to experts.

Scientists say by 1918, the ship would have vanished from site completely until it was later discovered buried during the examination of the 9/11 site.

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