A brick row house that is one of only two documented stops in New York City on the Underground Railroad has a new penthouse with oversized windows. Preservationists say the addition not only violates construction codes, it literally stands in the way of its rich history. The building at 339 W. 29th Street, once owned by the abolitionists Abby Hopper and James Sloan Gibbons, was among 12 row houses designated by the city's Landmarks Preservation Commission as a historic district in October 2009. That means no major exterior changes are allowed without approval. The inside had long ago been turned into a 10-unit apartment building. The current owner, Tony Mamounas, bought the building in 2004 and began renovations a few years later. He has said that he had permission from the buildings department to construct the extra floor before the home was declared a landmark, and he sued the city to continue the work and allow for tenants to move inside. <http://abcnews.go.com/US/wireStory/nyc-underground-railroad-site-court-battle-19907357> -- Bob Sullivan Schenectady Digital History Archive <http://www.schenectadyhistory.org/> Schenectady County (NY) Public Library