Revolutionary War artifacts unearthed at site of infamous colonial American heist: 'Very surprised'

Though it seems an unassuming plot of land in suburban Pennsylvania, the site was once home to colonial-era town buildings, including the county prison and courthouse.

The excavation, which took place from March 23 to March 28, focused on the area where the treasury building once stood.

The dig took place on land steeped in Revolutionary War history, according to Clint Flack, an exhibit specialist at Bucks County Historical Society.

The historian said they also found a small set of keys - either used for furniture or a padlock - as well as a Dutch copper coin called a duit and a New York penny from 1737.

Excavators also found a large amount of porcelain, pottery and glass that had been beneath the soil for over 200 years.

The team was "very surprised," said Flack, to find the treasury's foundation hidden just below the surface as well, which he described as being in good condition.

The foundation was a key find, as the building was the setting of an infamous robbery by the Doan Gang, a group of Quaker Loyalists who stole thousands in colonial currency in 1781.

The gang, many of whom were part of the Doan family, robbed the Bucks County treasury of a large sum - 1,200 silver Spanish dollars and 400 silver French crowns, as well as other cash.

"The robbery began at the home of county treasurer, John Hart, where the gang seized a bundle of cash that had not yet been deposited in the treasury as well as the keys to the treasury," Flack said.

The historian added that some of the outlaws held Hart hostage, while the other half of the gang robbed the treasury, just half a mile away.

"The gang unlocked the door to the treasury, but had to break open a locked desk by prying the drawers open with knives," he added. The desk is currently on display at the Mercer Museum.

Though the Doan Gang robbery remains a notable chapter, Flack said it's only one small part of the property's "incredible" history.

"Some of the Hessian [mercenaries] taken prisoner at the Battle of Trenton were imprisoned in the jail next to the treasury," Flack noted. 

"Multiple members of the Doan gang were imprisoned in the jail next to the treasury."