This project investigates the Kifisos river through an urban and ecological analysis and proposes measures for restoring the river, creating public space, and enhancing the cultural infrastructure along the two banks. The overall strategy posits the Kifisos river as a new cultural and ecological spine in the city, which mediates its infrastructural functions with its civic and environmental roles. An overall strategy is formed which addresses the ecological continuity of the river, flood mitigation, reconnection of the two banks, and construction of new buildings along the edges. In particular, new navigational and athletic paths are proposed along the restored river as well as sequences of public instances that respond to specific physical, infrastructural, and urban conditions. Smaller-scale proposals include a series of land formation strategies that respond to environmental and infrastructural situations. Last, four new institutional buildings are weaved at the edge of the river, on the basis of which public spaces are redesigned, thus redefining the relationship between urban and ground-topography, water, and vegetation.