The modernist Three Rivers Stadium—Pittsburgh’s “machine
for sport”—opened in 1970. Its circularity helped it convert between baseball and
football formats, to host both the Pirates and Steelers. But this circularity
also pushed fans for each sport farther from the field than had the Pirates’
Forbes Field and the oval Pitt Stadium, the Steelers’ home for the previous
decade. Allegheny Conference on Community Development Photographs, MSP 285,
Detre Library & Archives, Heinz History Center, Pittsburgh.