Proximity-centred accessibility—A conceptual debate involving experts and planning practitioners

Recognised as an important dimension of quality of life, accessibility has gained increasing attention from research and planning practice in the last decades. Rising concern with global warming and the dehumanization of cities has spotlighted the proximity-centred dimension of accessibility, which for decades has been mostly undervalued. In both research and practice, we witness a rise in references to proximity-centred accessibility, however, using a variety of different terms, with somewhat nuanced meanings or underlying concerns. Proximity-centred accessibility concepts are still in flux, inhibiting the establishment of a comprehensive understanding for the development of a cohesive research field and of effective public policies.

This paper provides a first contribution to the development of a conceptual framework for proximity-centred accessibility, through a co-development process involving both research and practice. For this we used a mixed methods approach incorporating bibliographic research, surveys, and a focus group, involving both experts in the research field and a sample of planning practitioners from Portugal and Germany.

Our research revealed over a dozen different proximity-centred accessibility terms currently in use in the scientific research field, of which, local accessibility and neighbourhood accessibility are the most commonly used. A difference in favoured terminology was identified between research and practice as well as different national contexts, requiring further explorations. While Proximity thresholds have been defined using a variety of physical distances or travel times, our survey revealed a nearly unanimous consensus around a threshold of 1600 m (roughly 20 min walking). Mixed evidence was found with regard to activities relevant at proximity. Regardless, playgrounds, green spaces, food shopping and elementary education showed particular relevance.

Building on the empirical evidence collected, we strike out a first conceptual framework for proximity-centred accessibility. Building on the general definition for accessibility, we include a maximum distance threshold of 1600 m to consider accessibility as proximity-centred. The proposed framework encourages multiple distances (up to 1600 m), transport modes, and activities (although the relevance of activities seems to be clearly dependent of distance and local context). The importance of clearly specifying the exact distances, transport mode(s) and activities for each application of the framework is stressed.