The increasing prevalence of physical inactivity across Europe poses a critical public health challenge, especially as it contributes to the rise of non-communicable diseases such as obesity, cardiovascular conditions, and diabetes; in this context, the spatial configuration of urban environments emerges as a fundamental determinant of active behavior, particularly walking, which has prompted researchers to develop tools capable of quantifying the walkability of different regions, with the aim of fostering more health-oriented urban planning strategies; this study proposes a standardized, high-resolution walkability index that captures the nuanced characteristics of the built environment across the European continent, incorporating seven carefully selected indicators—walkable street length, intersection density, green space availability, terrain slope, public transport access, land use mix, and 15-minute isochrone zones—all derived from harmonized geospatial sources including Sentinel-2, CORINE, OpenStreetMap, and NASA’s elevation models; the use of a 100x100 meter hierarchical grid combined with advanced spatial techniques like network buffers and distance decay functions allows for an exceptionally detailed analysis that remains scalable across vast territories, making it a versatile tool for both macro- and micro-level assessments; one compelling example is the identification of cities such as Barcelona, Berlin, Munich, Paris, and Warsaw as leading urban areas with high walkability, driven by compact forms, diversified land use, and rich connectivity—features that correlate strongly with higher levels of pedestrian activity; this index not only maps out existing disparities in walkability across urban and rural zones but also equips planners, policymakers, and health professionals with actionable evidence to guide future development toward healthier, more walkable cities.