“The Fourth River takes its name from a subterranean river beneath Pittsburgh, Pennsylvania, a city famously sited at the confluence of three rivers: Monongahela, Allegheny, and Ohio. This fourth river, unseen yet indispensable to the city’s riverine ecosystem, is actually an aquifer geologists call the “Wisconsin Glacial Flow”. The Fourth River literary journal grew up from the idea that between and beneath the visible framework of the human world and the built environment, there exist deeper currents of force and meaning supporting the very structure of that world.”