A piece of Manhattan history tied to the Underground Railroad may come crumbling down — but not without a fight.
A proposal to build a 100-foot-high commercial building next door to the Merchant’s House Museum, where a secret passageway used to smuggle slaves to freedom was discovered last month, is causing outrage in NoHo.
Experts say construction of the planned building will cause irreparable damage to the adjacent three-and-a-half-story site — listed on the National Register of Historic Places and the earliest known location of Underground Railroad activity in NYC.
“To find a previously undiscovered Underground Railroad site is the holy grail of historic preservation,” attorney Michael Hiller, who is representing the Merchant’s House, told The Post.
The Underground Railroad passageway — built in 1832 beneath a built-in dresser of drawers — is the only one in NYC that is accessible to the public, and the second to still exist in the city, aside from the Hopper-Gibbons House on West 29th Street.
Kalodop II Park Corp. wants to demolish a one-story garage it owns at 27 East 4th St. now being used to store food carts. It would be replaced with a nine-story office building that includes ground-floor space likely to be used for a restaurant or art gallery.
The developer had two previous applications for construction on this lot. The most recent was approved in 2023, years before the Underground Railroad was unearthed.
However, Kalodop never began the construction, and submitted new plans in December for a building with two more stories.
Since the lot is located within the NoHo Historic District Extension, which consists of 56 buildings that date back to as far as the 1820s, the Landmarks Preservation Commission must approve the proposal.
During a LPC public hearing March 17, Councilman Harvey Epstein (D-Manhattan), who represents the neighborhood, cited the potential collapse of the Merchant’s House due to the construction, and the threat to future discoveries that could be made around the Underground Railroad site, as reasons why Kalodop’s application should be denied.
The area is also home to the city’s first free black settlement in the 17th century — so it could be an African-American burial ground, preservationists warn.
“It may very well be right under the building next door,” Hiller said. “But if they excavate it, you’ll never find anything. They would be erasing black history.”
The Merchant’s House, now owned by the city, was built in 1832 and purchased in 1895 by merchant Seabury Tredwell, who lived there with his wife and eight children. It was turned into a museum in 1936 and has over 3,000 of the family’s belongings on display.
Both an architect and a structural engineer who are behind the proposed project were present at the hearing, and assured the construction will not damage the Merchant’s House, NYC’s only 19th-century home completely intact inside and out.
“Significantly, none of the representations made by the design professionals are made under oath. So, they can pretty much allege anything, and there are no consequences,” Hiller said.
The Merchant’s House hired structural engineer Michael Schuller to evaluate the project. He said it would cause cracks in the plaster throughout the interior and exterior of the museum and could also compromise the home’s structure.
Emily Hill-Wright, the Merchant’s House director of operations, explained at the hearing that since the construction will corrode its plaster, the museum would have to close to protect its staff, visitors and collection of artifacts.
The cost of the closing, which includes renting storage space, installing scaffolding and loss of revenue, is estimated to be over $4 million — funds the museum does not have, she added.
LPC commissioners could have rejected the proposal for the building at the public hearing by a majority vote, but did not.
The LPC told The Post it does not comment on applications currently under review.
There is no date set for the next meeting on the application.
In the meantime, the Greenwich Village Society for Historic Preservation created an online form where Merchant’s House supporters can email Mayor Mamdani and the LPC, asking them to save the museum.
Kalodop did not return a request for comment.