(Fast Company) — It’s hard to imagine any inch of New York City that hasn’t been scrutinized, glorified, surveyed, bought, and sold. But only 42 years ago, in 1968, Pratt Institute Professor Jim Hurley discovered three buildings in Brooklyn completely off the grid. He was in a helicopter, preparing for his urban studies course when he spotted three ancient houses along a forgotten alley. It looked like a little farm airlifted from Middle America. Instead, it was an improbably intact remnant of Weeksville, the country’s first community of free, black Americans. Four decades after that discovery and nine years in the making, those three 120-year-old houses are being preserved in a remarkable $32 million museum, community center, and green space which will open next summer. Located in the Crown Heights neighborhood of Brooklyn, the site occupies what was once Hunterfly Road, a 320 year-old Dutch and Indian trading route. The project to preserve it and the houses above is an amalgam of work from architects, landscape architects, historians, city planners, and the museum’s staff.