The article traces the recent ‘discovery’ of the importance of walking in urban green spaces to health to its historical roots, and situates it within its discursive and political–economic context. It shows, using the UK as a case example, how the nineteenth century urban parks movements had public health as one of its key objectives, linked to a hegemonic middle class project of promoting order and ‘rational recreation’ to the working classes. It then shows that as health problems and understandings changed, along with broader political–economic shifts, park aims shifted from enhancing ‘health’ to promoting ‘fitness’. With the growth of modern notions of citizenship, decline of infectious disease, and the rise of the biomedical model in the welfare state era, parks ceased to be seen as means to health and were transformed into municipal services. After the oil crises of the 1970s and the rise of Thatcherism, they went into decline, though from the 1990s there were political efforts to revive them as part of a wider set of sustainable urban policies, and growing preoccupations with the health costs of a sedentary and obese society. In this context, the article provides a critical commentary on the science and policy of individualist discourses of ‘green walking’ and health. It argues for a broad ‘ecological health promotion’ approach, using economic crisis as an opportunity to move forward in ways consistent with environmental justice and an emancipatory ‘capabilities’ approach to public health.