Metabolism of Cities: Fourth Edition

What is now Metabolism of Cities started out as an academic side-project in 2014, initially named MFA Tools. The initial goal of the website was to catalogue relevant Material Flow Analysis (MFA) literature, and to build a community around this open source platform. In 2015, a new version of the site goes up under the name of Metabolism of Cities, due to the fact that the first collaborators all had urban-scale material flow interests. Over the years, people from various backgrounds and locations joined in, and the website continued its expansion.

After a first dedicated meetup in 2018, most people in the team (now seven strong) came together to discuss how to improve and grow the website. A new version of the site was launched later that year, with an ever-growing collection of sections with centralised information, collected as well as in-house created multimedia and now also a dedicated section for curated data. This focus on urban metabolism data, through a project named MultipliCity, was a core pillar of the new website, and a prototype system was set up to find out how to best set up city data dashboards.

After almost two years of experimenting, Metabolism of Cities is now launching an entirely new version of its website. Now in its fourth edition, the website deviates quite strongly from previous iterations. Some of the key aspects include:

  • Independent "sub-sites": the depth and complexity of the navigation menus in the previous website were an indication that the site's content had outgrown its framework. It was easy to miss large parts of the website by simply not noticing a single entry in the navigation menu. Furthermore, some sections had their own target audience and creating a separate identity seemed to make most sense. The new system works primarily with subdomains (like, and through consistent branding in headers and footers the link with Metabolism of Cities is retained.
  • Community portals: in all previous editions of the website, visitors were encouraged to join the community. However, being driven by a global collective of volunteers it became harder and harder to promptly and fully respond to the growing interest. In an effort to streamline the onboarding process, and in an effort to more openly share what happens "behind the scenes", there is now a Community portal in every subsite. These community portals explain how people can join, and allow for immediate signup. The current to-do list is shown to all, and anyone can hop onto a task and get going. Various commenting and discussion spaces were made available so that most if not all internal discussions can be part of the websites and shown online.
  • Newly structured data hub: now rebranded from the MultipliCity project to the Metabolism of Cities Data Hub, a fully restructured system is now in place to take the city data dashboards to the next level. After experimenting with data for a variety of cities (and islands!), the system was revamped quite significantly to better cater to the challenges and nuances that can only be found out after practicing such a system. In the new system there is a better-structured workflow that goes from data collection, to data processing, and lastly to data analysis. This workflow is being embedded throughout the website, and the new system will be launched in phased approach, starting with the data collection system.
  • Online course integration: after having launched an online course on urban metabolism for policy makers in 2017, a new online teaching system was embedded in the website. Rolled out as part of the Education Hub, two new free and open courses are available to all. These courses are the first installment of a series that is directly coupled with the data hub, and participants of the courses will work on data collection, processing, and analysis -- while contributing to the open source data hub at the same time.


Within the new website, there is a strong focus on the various projects that Metabolism of Cities has engaged in or is actively working on. Each project either has its own website (the aforementioned "sub-sites"), or it has a project page on the main website. Visitors are encouraged to check out the project list to see all projects, and to visit the various new project websites:

Together with our colleagues who run sibling website Metabolism of Islands, Metabolism of Cities is looking forward to putting the new system to use and trying out the many new tools and features that have been and continue to be built.

A warm thanks to all those people who have worked long and hard to make this new system a reality, and who continue to make Metabolism of Cities a friendly, encouraging, and inspiring digital home for many.