Mental health issues are becoming ever-more common in contemporary societies as urban landscapes are over-stimulating and stress-inducing. Studies suggest that lacking access to green infrastructure may be a fundamental factor. In post-industrial cities and health care systems, nature’s healing abilities are however commonly neglected and have only recently become subject to scientific research. This project explores how health is impacted by the built and natural environment. Caused by the environmental crisis and dynamics of the global market, many European port cities are in transition leaving the territory vacant and afficted with industrial leftovers. In Dunkerque, the former refinery grounds bordering the old habour are such vacancy. Stricken with remnants of an industrial past, both structural and in form of contamination, they have been abandoned and become in a sense wild. At the same time, they are testimony to the city’s relationship with the North Sea that has been shaped by its industrial heritage as well as historic war events drawing an invisible boundary between land and water. Seizing the void, this project comprehends an urban garden and a mediator of health; environmental, socio-cultural and human health alike. As a novel form of green infrastructure it endeavours to renegotiate existing thresholds – between the inhabitant and the territory, the city and the port of Dunkerque, between land and sea – to become a piece of collective conscience of place, nature and health. Through a sequence of gardens, the visitor is invited to reconnect to and explore the natural world present in a place so foreign to nature due to its anthropomorphic history and heritage. It is precisely this atmosphere that grants a new perspective on the vegetative actors of the place and not only stimulates a re-joining with the territory but also with the inner self. The territory itself is subject to remediation through the vegetation on site. Phytotechnologies degrade substances and allow a subtle opening of the site through time. By that, hitherto marginalised port areas and the North Sea foreshore are increasingly reconnected with the city converting the site into a link between land and sea.