Heidelberg discusses sustainable urban development: solutions from Cologne and Karlsruhe!

Heidelberg discusses sustainable urban development: solutions from Cologne and Karlsruhe!

On October 23, 2025, the fourth specialist evening on sustainable urban development took place in Department 16 in Heidelberg. The event, which is part of the “Urban Development in Dialogue” series, was dedicated to the discussion about resource-saving use of land in times of urban growth. Great inspiration came from Dr. Sebastian Eichhorn from ILS Dortmund, Inga Hoffmann from the city of Cologne and Oriana Krämer from the city of Karlsruhe. MRN News reports that the panel discussion particularly focused on strategies for multiple interior development, reducing land use and climate-adapted urban design.

“Dynamic development and economical use of land” are central themes of the Heidelberg 2035 urban development concept, and this is exactly where the challenge lurks: How do you organize population growth and new settlements of science and business efficiently? Dr. Eichhorn gave a deep insight into the problem by pointing out the high level of new use of space for single-family homes in cities such as Frankfurt and Münster, where over 90% of the new space is occupied by this. The aim is to create more density and more diverse forms of housing through a system change and legal anchoring - this point in particular was discussed intensively during the discussion.

Cologne is moving forward

The city of Cologne is already relying on the concept of “quality density”. With differentiated neighborhood typologies and the new “Cologne Catalog Inventory” it has launched eleven strategies for internal development. The goal is clear: more living space through clever use of existing space and the creation of livable neighborhoods. This shows that urban planning in Cologne is already on a promising path.

But the topic goes beyond the city limits of Cologne. The city of Karlsruhe is also responding to current challenges, such as heat stress. She has developed a green bylaw and an unsealing concept for the city center to counteract the urban heat island effect. Fraunhofer IBP reports on the need to create green spaces, establish fresh air corridors and targeted shading measures to reduce heat in cities. Urban space must be adapted to climatic changes in order to improve the quality of life of citizens.

Synergies and legal framework conditions

The need for a regional approach to solving the housing shortage was another point of discussion at the event. Surrounding communities could make a significant contribution through more compact, neighborhood-based developments. Investors are becoming increasingly interested in the idea of ​​dense, sustainable neighborhoods with high-quality infrastructure and quality of stay.

In this context, the importance of targeting owners and investors in existing areas was also highlighted. However, in order to successfully implement these approaches, a clear legal framework is required that promotes the transformation of urban areas. Difu explains that many land use plans are outdated and often do not provide the necessary incentives for effective internal development. An effective land use planning tool can make an enormous contribution to overcoming the upcoming urban development challenges.

In summary, it can be said that the cities of Cologne, Karlsruhe and Heidelberg are on a promising path. By exchanging ideas and developing joint solutions for housing shortages and climate adaptation, they are already painting a picture of sustainable urban development. The dialogue must be continued and the legislative framework must be adapted in order to better leverage the potential of internal development and to make urban space sustainable.