Today’s cities face numerous challenges—human, environmental, and spatial. Integrating greenery into architectural design introduces new ways of interacting with the environment, while also enhancing human well-being and building functionality. While the theoretical statement Living with Greenery was exploring its integration & impact into buildings in urban spaces, this project proposes the transformation of the former Sébeillon railway site in Lausanne into an urban park and collective housing, integrating vegetation at two scales: urban and architectural. At the urban scale, the project reconnects existing environmental and accessibility networks, especially toward the south. The design introduces a large urban park that links surrounding natural elements. This landscape continues into the built environment, entering the residential structures and extending through the Grand Hall of the existing building, where an indoor garden is created. At the architectural scale, the focus is on translating the direct relationship with nature, typically found in individual dwelling, into a collective context. The former merchandise halls are transformed into housing units and shared workspaces that remind of the industrial past. New buildings on the site incorporate green courtyards and facades with planted balconies, allowing residents to live closely with greenery. Overall, the project seeks to redefine interactions between people and the built environment, but also between humans and other living beings.