"We had no idea any of that was there," he continued. "We always thought those back buildings [including the house kitchen] were built on very shallow foundations. Now we can see most of the kitchen is there and the entire kitchen had a basement."
In addition to the unexpected finding of kitchen foundations, the excavation also has uncovered the rear wall of the main President's House, which stood at the southeast corner of Sixth and Market Streets until it was largely demolished in 1832.
Three commercial buildings then were constructed on the site, and the excavation has uncovered their foundations as well.
In fact, in one of the exciting moments of the dig, archaeologists broke through the cement basement of one commercial building last week and there, right on top of a remaining President's House foundation wall, was an 1833 penny. It was common practice for builders to place a properly dated coin beneath new construction - and the commercial building was, in fact, erected in 1833.
"It's unbelievable that we came down right on top of that, but it certainly dates it very accurately," Mooney said. "We couldn't believe it when that popped up. Sometimes you imagine what would be a really cool find, and sometimes you can't even predict."
In another unusual and unexpected discovery, archaeologists found another President's House foundation wall running from the main house, which fronted Market Street, back to the kitchen, 50 to 60 feet to the rear. It suggests strongly that there was a subterranean passage from the house basement to the kitchen basement, which would have been used to move food and goods without leaving the house.
At the back of the kitchen, an even deeper subbasement area was discovered that may have been a cold cellar or Washington's wine cellar.
Other findings so far include three so-called "shaft features."
