15-min cities : Bringing more proximity in cities

The case for integrating urban experiences in the 15min city concept.

Some argue the 15-minute city is ‘old wine in a new bottle’. Yet it is a powerful concept because it refocuses urban design around proximity principles: the goal is to ensure access to all basic needs within a 15-minute walk or bicycle ride, therefore giving explicit priority to active mobility. From a sustainable mobility planning perspective, the 15-minute city aligns with the ‘Avoid’ strategy – reducing the need for long-distance, high-carbon travel - together with the ‘Shift’ strategy – encouraging the use of more sustainable transport modes - as defined by the UNDP and by David Banister’s seminal ‘sustainable mobility paradigm’ contribution [1]. These strategies are now also central to SDG 11 on sustainable cities and communities. In other words, the best way to achieve zero-carbon mobility is by minimising the need for motorised travel altogether.

But why 15 minutes? Research on travel behaviour and travel time budgets shows that people typically spend around 70 minutes per day travelling [2]. A 15-minute access time allows for multiple daily trips - for work, shopping, healthcare, entertainment, or visits to social and natural spaces -although 15 minutes does not need to be a fixed rule. The benefit: it offers a simple, relatable guideline for reducing distances to an acceptable, ‘reasonable’ travel time [3], [4]. It is also a powerful and direct way of communicating this concept among stakeholders, citizens, policymakers, and politicians, as it simplifies and condenses a complex idea. The downside: it stems from the traditional view in transport planning that time is everything and that all travel time is inherently wasted.

So what about people? In an interview earlier this year, Carlos Moreno shifted his focus to “sustainable cities of happy proximities” – or happy polycentric proximity*. The idea draws from Danish architect Jan Gehl’s seminal book Cities for People, which explores what makes cities and streets visually and socially appealing. In our review paper on worthwhile travel time (WTT), we unpack what makes travel time valuable from the perspective of individuals and travellers: enjoyment, productivity, and health [5]. Importantly, the WTT concept extends beyond just movement. It also applies to 'urban time,' even when stationary—such as sitting on a bench—where the experience of time contributes to quality of life. We believe this concept is well suited to the 15-minute city 2.0, where the experiences of citizens and travellers takes centre stage.

This focus on experiences opens two key research paths. First, how can we measure the quality of experienced time, both during multimodal door-to-door trips and in stationary moments, within complex urban environments? This is particularly important when considering the perspectives of diverse individuals, including vulnerable road users such as pedestrians, cyclists, the elderly, and children. Are there unobtrusive methods that move beyond traditional stated-preference surveys, or, as demonstrated in our research, app-based questionnaires triggered by real-time trips? [6]. Second, if such data can be collected, how can we effectively integrate it into mobility, urban planning and decision-making to improve quality of life in the city?

If you are working on similar topics, do reach out! 

[1]      D. Banister, “The sustainable mobility paradigm,” Transp. Policy, vol. 15, no. 2, pp. 73–80, Mar. 2008, doi: 10.1016/j.tranpol.2007.10.005.

[2]      A. Ahmed and P. Stopher, “Seventy Minutes Plus or Minus 10 — A Review of Travel Time Budget Studies,” Transp. Rev., no. September 2014, pp. 1–19, Aug. 2014, doi: 10.1080/01441647.2014.946460.

[3]      D. Banister, Y. Cornet, M. Givoni, and G. Lyons, “Reasonable Travel Time – The Traveller’s Perspective,” in A Companion to Transport, Space and Equity - NECTAR Series on Transportation and Communications Networks Research, R. Hickman, B. M. Lira, M. Givoni, and K. Geurs, Eds., Edward Elgar publishing, 2019, pp. 1–15. [Online]. Available: https://www.e-elgar.com/shop/the-elgar-companion-to-transport-space-and-equity

[4]      D. Milakis, R. Cervero, B. van Wee, and K. Maat, “Do people consider an acceptable travel time? Evidence from Berkeley, CA,” J. Transp. Geogr., vol. 44, pp. 76–86, 2015, doi: 10.1016/j.jtrangeo.2015.03.008.

[5]      Y. Cornet, G. Lugano, C. Georgouli, and D. Milakis, “Worthwhile travel time: a conceptual framework of the perceived value of enjoyment, productivity and fitness while travelling,” Transp. Rev., vol. 42, no. 5, pp. 580–603, 2022, doi: 10.1080/01441647.2021.1983067.

[6]      Y. Cornet, M. J. Barradale, J. J. Bernardino, and G. Lugano, “Worthwhile Travel Time: Design Challenges of Capturing the User Experience by Smartphone,” 2019 Smart Cities Symp. Prague, SCSP 2019 - Proc., pp. 1–9, 2019, doi: 10.1109/SCSP.2019.8805706.

* https://www.archdaily.com/1016337/a-framework-for-developing-happy-proximities-in-conversation-with-carlos-moreno-the-pioneer-of-the-15-minute-city