Greenbelt Knoll is a residential development in the Northeast section of Philadelphia, Pennsylvania. Planned and built from 1952 to 1957, it is notable as the first planned racially integrated development in Philadelphia and among the first in the United States. The developer, , a leader of the open housing movement, required that 55 percent of the homes be sold to whites, and 45 percent to non-whites. The first house sold in 1956 for $20,000. The isolated little neighborhood included its own swimming pool, which was filled in circa 1985, leaving no trace above ground.