The controversy over the partial demolishment of the Nangang Bottle Cap Factory for redevelopment is a prime example of the ongoing public debate about urban renewal in Taipei. The controversy crystalizes the tension between a growing public desire for historical preservation in Taipei to safeguard shared history and restore collective memory, and profit‐driven capitalistic development. The transformation of the factory over the past decade—from disused public property to a city‐operated Urban Regeneration Station for fostering art and innovation, and finally to a demolition site that is being readied for new construction—illustrates the tug of war between the exigencies of cultural/historical preservation and urban renewal in Taipei. During the process, not only did citizen activists play a major role in raising the public’s awareness of the unique value of the Nangang Bottle Cap Factory as one of the last major relics of Taipei’s industrial heritage, graffiti artists also created works in the abandoned factory that dialogued about its contested future under a neoliberal capitalist regime. By tracing the origins of the controversy, I argue, through a photo documentation of the accumulated graffiti inside the factory before demolition began, that the factory “ruin” has functioned as a theater for diverse forms of guerrilla urbanism, including engaged art, urban exploration, and community organization.