Crews are working to unearth a time capsule that historians think is hidden in a cornerstone of the Massachusetts State House, WBZ radio reports.

The time capsule might have been buried by Paul Revere and Sam Adams in 1795, WBZ and the State House News Service report, based on records detailing a ceremony when the capsule was buried.

If true, this would be by far the oldest unopened time capsule on record, leaving famous ones like the 1939 Westinghouse time capsule far behind.

Workers trying to figure out the source of a water leak found the location of the capsule, the State House News Service reports.

The capsule has been unearthed once before, in 1855 while repairs were being made to the State House. It was then put back in its place and left there, the State House News Service notes.

Here’s a look at crews working to find the capsule:

This wouldn’t be the first time an old time capsule was found in Boston.

Earlier this year, crews doing restoration work in the old State House, which is now a historical museum, found a time capsule from 1901 hidden beneath statues of a lion and a unicorn. The capsule contained letters, photographs, and newspaper articles in mint condition, according to NECN.

Back in the 18th century, the old State House was “the center of Boston ‘s civic life” and “the scene of some of the most dramatic chapters in the lead-up to the American Revolution,” according to The Bostonian Society.

UPDATE: This post has been corrected to clarify the difference between the two Massachusetts State House buildings.

 

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