Sample data catalogue provides first-ever overview of open data in communities


Population growth, free parking spots, drinking water quality: Many of the digital pioneers among Germany’s municipalities publish local-level information as “open data.” For the first time, a new sample data catalogue provides an overview of data that German communities are making available to the public. As an initial step, the online catalogue offers information on cities and towns in the state of North Rhine–Westphalia.

The Covid pandemic has shown how important up-to-date and freely accessible data can be for making decisions. German policy makers, for instance, have been partially basing their responses to the pandemic on the number of people who have contracted the illness, figures that communities have been making publicly available. Yet freely accessible data are also relevant to the future development of the country’s communities even when no crisis is taking place.   

A new sample data catalogue now offers for the first time an overview of which data sets are being made available by Germany’s cities and towns. The online catalogue has been developed by us in collaboration with the data portal GovData, the Open Knowledge Foundation and KDZ – Centre for Public Administration Research. As a first step, the catalogue contains the generally accessible data sets published by communities in the state of North Rhine–Westphalia

Open data in the smart city

Public administrators in several pioneering communities have been releasing open data for a number of years. The non-personal data cover a range of areas, such as local-level statistics, public transport and the environment. They are available in an open format and anyone can use or disseminate them freely.  

The data can be deployed to develop a range of applications, such as depictions of a community’s drinking water quality or apps that access open transport data to provide the optimal combination of transportation options. Of the 20 cities that top the Smart City Index published by Bitkom, the trade association of the German information and telecommunications industry, 16 have their own open data portal.

Catalogue fills gaps in use of community data

Until now, a reliable overview was lacking of which data are being published by Germany’s cities and towns. Anyone who wanted to access open data that went beyond more than one community had to invest considerable time finding out what was available. Moreover, it was hard for municipalities to know which data would be suitable for release to the general public. Our sample data catalogue has allowed us and our project partners to close those gaps.

The catalogue brings together all the information that cities and towns in North Rhine–Westphalia make available as open data on the Open.NRW portal. It does not contain the actual data, but groups them using metadata and provides information on where they can be found in local sources. 

Until now, some 80 communities in Germany, including many major cities from Kiel to Munich, have released open local-level data. Approximately half of those communities are in North Rhine–Westphalia.

The Open.NRW office was part of the team that developed the sample data catalogue. The data portal run by the NRW state government also designated the catalogue as a milestone, which the state committed to as part of the second national action plan adopted for the Open Government Partnership.

Ideas for more open data

The sample data catalogue groups the data sets by approximately 60 different community-related subjects. Anyone looking for generally available information can use the catalogue to view all open data offered by a specific city or town, or the open data different communities release on a specific topic. This facilitates comparisons and can provide communities with ideas for publishing additional open data as well.

This key advantage is also emphasized by Alice Wiegand, project manager for open data in Düsseldorf, the capital of NRW, who helped develop a prototype of the sample data catalogue.

Open data guide for communities

In parallel to creating the sample data catalogue, the project partners also developed a machine learning model. The model is meant to facilitate automatic updates of the sample data catalogue. In addition, it can be used to create a catalogue that covers all open data communities in Germany. It is not currently clear, however, when this will happen.

In addition to the sample data catalogue, we have also published an open data manual on the website The manual makes it easier for cities and towns to familiarize themselves with the topic of open data, since it gives a clear and concise description of the most important steps a community must take to make open data accessible. We also publish a brochure which briefly describes what is meant by open data at the local level, i.e. open administrative data. It outlines several arguments in favor of open data from the perspective of public administrators, the general public and the business community. It also provides examples of how open data can be used.

“The sample data catalogue is a treasure trove of choice data maintained by public administrators – data that are just waiting to be published by other communities.” Alice Wiegand, City of Düsseldorf

Alice Wiegand, Stadt Düsseldorf

A joint project with communities in NRW

The sample data catalogue is a joint project by the Bertelsmann Stiftung, GovData – The Data Portal for Germany, the Open Knowledge Foundation Germany and KDZ – Centre for Public Administration Research (Austria). A number of communities, such as the cities of Cologne, Bonn, Düsseldorf, Moers and Freiburg, participated in the creation of a prototype released in May 2019, as did the Open.NRW office at the NRW Ministry for Economic Affairs, Innovation, Digitalization and Energy. The sample data catalogue can be accessed at