Mapping point and line densities of cross-border governance: the example of the Interreg cooperation programme

Cross-border cooperation has become a key dimension of European integration, supported extensively through EU-Interreg programmes. Yet, the growing density of actors and interconnections creates methodological challenges for mapping and interpreting cross-border governance at the European scale. This article addresses the question of how point- and line-density approaches can represent cross-border governance structures using keep.eu data from Interreg V-A (2014–2020). Based on 5,618 projects and 17,929 partners, GIS-based kernel density methods are applied to compare partner concentrations and cooperation networks across Europe and in three case-study regions. The findings show that point density effectively represents the spatial concentration of actors, while line density better captures the directionality and intensity of cooperation axes, particularly in maritime and large-scale border regions. The study demonstrates that combining both approaches provides a more comprehensive understanding of European cross-border governance and supports evidence-based spatial development. KEY POLICY HIGHLIGHTSThe results support in particular EU regional policy development, allowing for improved territorial evidence.Point and line density visualisations provide complementary insights into European cross-border cooperation. Point density identifies concentrations of actors and funding, while line density reveals the structure and intensity of cooperation networks.The suitability of each method depends on geographic context and policy objectives. Line density is particularly useful in maritime and large-scale border regions, whereas point density better reflects settlement structures in urbanised and mountainous areas.Density-based mapping helps identify cooperation hubs, territorial imbalances, and underutilised connections, enabling more targeted Interreg investments and strengthening long-term cross-border governance capacities across Europe. The results support in particular EU regional policy development, allowing for improved territorial evidence. Point and line density visualisations provide complementary insights into European cross-border cooperation. Point density identifies concentrations of actors and funding, while line density reveals the structure and intensity of cooperation networks. The suitability of each method depends on geographic context and policy objectives. Line density is particularly useful in maritime and large-scale border regions, whereas point density better reflects settlement structures in urbanised and mountainous areas. Density-based mapping helps identify cooperation hubs, territorial imbalances, and underutilised connections, enabling more targeted Interreg investments and strengthening long-term cross-border governance capacities across Europe.