The European Environment Agency (EEA), through its European Ground Motion Service (EGMS), required a trusted and authoritative background map layer to enhance the interpretability of ground motion data across Europe. While EGMS provides millimetre-accurate insights into geohazards such as subsidence, landslides, volcanic unrest, and human-induced movements, many users find maps more intuitive than satellite imagery when identifying urban structures, roads, and bridges. To address this, the EuroRegionalMap (ERM)—a harmonised, seamless topographic open dataset created by 31 European National Mapping, Cadastral and Land Registration Authorities (NMCAs)—was integrated into the EGMS data viewer. Delivered through the Open Maps for Europe (OME) interface, this dataset provides a consistent, reliable, and authoritative background layer for users to contextualise ground motion measurements across national borders.