A new EU-backed study is investigating how Europe can create healthy and sustainable urban environments. The study aims to chart out the types of cities Europe has, and which are best for human health, the environment and low carbon emissions. The project is being coordinated by the Barcelona Institute for Global Health (ISGlobal).

Researchers from the EU-funded UBDPOLICY project have identified four basic urban configurations in Europe and compared parameters such as air quality, mortality and emissions. Their findings have been published in London-based The Lancet Planetary Health.

The four European city types are compact, high-density cities, open, low-rise, medium-density cities, open, low-rise, low-density cities and green, low-density cities.

After studying these cities, the researchers found that compact, high-density European cities tend to have poorer air quality, lower availability of green space, higher mortality rates and a greater urban heat island effect compared to less dense cities. However, their carbon emissions per capita were considerably lower than those of low-density, green cities.

With their small surface areas and high population densities, high-density compact cities such as Milan and Paris have the largest number of inhabitants in Europe overall.

Dense public transport networks and cycling and pedestrian infrastructure in these cities facilitate short-distance mobility. Compact cities are therefore considered the best theoretical model for promoting healthier and more sustainable cities.

“After analysing more than 900 European cities, we believe that, as suggested by published data and experts, the compact city may continue to be the model of the future, but in its current configuration it shows low environmental quality and needs to overcome important challenges,” said study co-author and ISGlobal researcher Tamara Iungman.

The possibility of reducing car dependency, accessibility on foot or access to services and opportunities for social interaction are clear advantages of the compact city model. However, compact cities still show a high presence of motorised transport and a clear lack of green spaces.

Among the four types of cities, compact cities with high density and open cities with low height and medium density have the highest motorised traffic flows, which leads to greater exposure to air pollution and a more pronounced urban heat island effect. These cities also have the highest mortality rates.

However, the advantage of concentrating people and services in a smaller space is greater energy efficiency, which is why compact cities are also the type of city with the lowest CO2 emissions per capita.

According to the study’s lead author Mark Nieuwenhuijsen from ISGlobal, “We must harness the potential of our compact cities through innovative models, such as superblocks, low-traffic or car-free neighbourhoods, incorporating alternatives such as nature-based solutions, including tree planting and green roofs and facades. It is essential to reduce car use and invest even more in active and public transport. Of course, there is no one-size-fits-all solution for all cities. Each city must carry out specific studies based on its own characteristics and design a solution according to its needs to find the optimal model in terms of health, environmental quality and carbon footprint.”

The UBDPOLICY (THE URBAN BURDEN OF DISEASE ESTIMATION FOR POLICY MAKING) project ends in 2026.