In Episode 4, we explore how the built environment—and trees—impact communities. Renowned landscape architect Frederick Law Olmstead designed Buffalo, New York, around its parks, and it was once considered the best-designed city in America. But in the mid-20th century, one of his parkways was torn out and replaced with a highway that connected downtown with the new suburbs, in the name of urban renewal. We explore the impact of the highway on the surrounding community and traffic safety for automobiles and pedestrians alike. The city plans to put a cap on the highway to restore the urban parkway—and Frederick Law Olmstead's vision. But is it too late?