NEW YORK, NEW YORK—Researchers from the Tree Ring Laboratory at Columbia University analyzed samples taken from the partial hull of a wooden ship discovered 22 feet below street level at the site of the World Trade Center in lower Manhattan in 2010. Hickory in the keel helped them to narrow the search for the ship’s origins to the eastern United States. White oak in the ship is similar to samples from a study of Philadelphia’s Independence Hall. “We could see that at that time in Philadelphia, there were still a lot of old-growth forests, and [they were] being logged for shipbuilding and building Independence Hall. Philadelphia was one of the most—if not the most—important shipbuilding cities in the U.S. at the time. And they had plenty of wood so it made lots of sense that the wood could come from there,” Dario Martin-Benito of Columbia’s Tree Ring Lab told Live Science. Most of the ship’s timbers were sent to the Maryland Archaeological Conservation Laboratory. For more on the discovery of the ship, read ARCHAEOLOGY's feature "The Hidden History of New York Harbor."