The plan is a renovation project for a historic district. The building frontage is 150 meters long, consisting of 11 courtyards of different sizes. The existing buildings are basically abandoned. We have applied the theory of" symbiosis", shaping public spaces in three dimensions. It accommodates complex uses such as commerce, cultural tourism, and residence, transforming the spatial structure of modern collective residential courtyards into flexible and variable experiential spaces, providing ideas for the reuse of architectural heritage in historic urban areas under stock renewal.