Yet another case of an age-old ship sunken into mire has been found. In this case, it's from as far back as the Revolutionary War era--exciting.

Archaeologists stumbled upon the ship remains in Potomac River mud, while performing a survey of a new hotel site in Alexandria, Virginia, in the Washington, D.C. suburbs., according to an article in Smithsonian. The ship may reveal much about how 18th century colonists here in North America constructed their boats.

Not long ago, at the same site, archaeologists and construction crew found an 18th century warehouse's remains, which they think was the first public building in Alexandria. The city was founded in 1749. The warehouse, though, was present on historical maps of the local waterfront; the shipwreck was noted nowhere and was a surprise find.

"It's very rare. This almost never happens," as archaeologist Dan Baicy said, according to a Washington Post article. Baicy works for Thunderbird Archaeology, which is excavating the construction site. "In 15 years that I've done this work, I've never run into this kind of preservation in an urban environment where there's so much disturbance."

While it's true that late-18th century workers used sunken ships to aid in the landfill process to lengthen the waterfront, as an Old Town Alexandria Patch article noted, finding two historical finds at the same site is important.

Researchers suspect the ship could have been a cargo ship or military vessel. It will be documented with 3D scans, photos and drawings while still on site, then it will be removed to tanks of water until further study can take place in a preservation laboratory.

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