Cities are in a perpetual state of becoming and are never finished. The wet dreams of urban planners and architects to conceive and deliver the ultimate city vision in one go are now moribund. To design cities which are equitable and sustainable we need to make cities differently: an urbanism that is intentionally incomplete.

To achieve this, we propose a different process of urban design in order to change who the city is for and how it is made – open urbanism – through which we can establish the state of change as the starting point for its future. Our collaborative practice of open urbanism understands and celebrates the existing city as unfinished and identifies an ecosystem of strategies and methods for asking new questions for how and why the city can be transformed. It is able to operate across a range of scales from the microcosms of growth and decay on surfaces, through the human scale, and to the macro urban district.

We are working with built environment professionals, urban regeneration developers, creative practitioners, and local communities to develop trajectories that are inclusive and transitory for the co-creation of the future city. The context for this work is Manchester, UK. The world’s first shock city due to industrialisation is now going through its second shock city state as we uncover ambiances and elements that have not been presenced since 1780. Our practice-based research focuses on the area of Mayfield, now a major urban regeneration programme, that has been out of sight and out of mind for many decades. In the interim it has evolved its own unfinished patinas and landmarks: as the grout in masonry slowly flowers over 150 years; trees emerge from walls; and lost gardens and a culverted river are revealed.

Our establishment of open urbanism practices and new urban regeneration processes recognises the value of atmospheres and transitional situations. Rather than cleaning these up, they become the basis for supporting a provisional city that becomes the stimulus for further transformation. To illustrate our work, we share two strands of our thematic practice: ephemeral archaeology and dark design. Both are active and experimental methods that enable new and vital narratives and species of space to be explored, embracing the city in flux. We then present a wider set of practices and principles for the intentional design of unfinished cities as a means to investigate the future, where the ongoing accretions and disappearances are adopted as urban design values.