The excavation at the historic President's House site, 6th and Market streets, has taken an interesting turn.
Archeologists at the site found amid the fill a coin from 1833, confirming that the house was torn down in 1832, they say, and also located significant kitchen and foundation walls.
"We're very excited," said National Park Service Archeologist Jed Levin. "In archeology, you never know what you're going to find until you dig. It was a long shot that any portion of the house would survive. And now we're learning things we might otherwise never have known.
"Based on documentation, we thought the President's House kitchen was only one story, so we didn't expect it to have deep foundations. But now we know it also had a basement. This makes sense since it may have been used for storage."
From 1790 to 1800, the house was used by George Washington and then his successor, John Adams. While Washington was president, the house was also home to eight slaves, a discovery made by historian Edward Lawler Jr. in 2002.
The site is being combed over for artifacts, but by next year will be transformed into a permanent, $5.1 million exhibit studying slavery and the presidency. Philadelphia-based Kelly/Maiello Architects and Planners was named lead designer for the project.
For now, visitors can view the archeological site from an observation platform, not far from the entrance to the Liberty Bell.