The European Plate Observing System (EPOS, www.epos-eu.org) has been meticulously designed and established as the only European Research Infrastructure dedicated to solid Earth science. EPOS aims to address the prevailing fragmentation and to ensure seamless coordination of efforts and priorities among European nations. Its mission is to provide sustainable, long-term, and open access to solid Earth science data and services integrating diverse European Research Infrastructures under a federated framework. The harmonized integration of solid Earth science data is crucial for developing new concepts and tools for enabling excellent science, a precursor for contributing to current societal needs connected to the Earth system. Aggregated data, made open and universally accessible, is key for conducting trans-disciplinary studies to address societal challenges like sustainable use of resources, climate change, and clean energy transition. The EPOS Science Program, included in the EPOS ERIC Strategy 2024-2028, foresees the following strategic objectives: Ensuring smooth and seamless access to solid Earth science data and services; Enhancing and advancing services for solid Earth science; Enlarging, widening and empowering the user community; Implementing principles of Open Science and FAIR data management, and contributing to e-science innovation; Amplifying and spreading the societal value of EPOS; Boosting global cooperation. EPOS is a distributed Research Infrastructure that integrates and ensures usability of multidisciplinary solid Earth science data and services belonging to diverse scientific communities (currently, Seismology, Near-Fault Observatories, GNSS Data and Products, Volcano Observations, Satellite Data Products, Geomagnetic Observations, Anthropogenic Hazards, Geological Data and Modelling, Multi-Scale Laboratories, Tsunami) and generated by over 250 national research infrastructures from 26 European countries. On October the 30th 2018, the European Commission granted the legal status of ERIC to EPOS. Today, EPOS ERIC has 19 members (Austria, Belgium, Bulgaria, Croatia, Denmark, France, Italy, Greece, Iceland, Norway, Poland, Portugal, Romania, Slovenia, Spain, Sweden, Switzerland, The Netherlands, the United Kingdom) and one observer (Germany). EPOS offers a multidisciplinary research platform that provides open access to harmonized and integrated scientific data and products, all anchored in the FAIR principles. Main users of EPOS Research Infrastructure are scientists, in solid Earth science and other environmental disciplines, IT experts, and concerned governments. Originally designed to meet the needs of these reference communities, it matured into a fully-fledged infrastructure facing the challenge of expanding its user base numerically and diversifying its users. Current plans involve integrating additional scientific communities, non-academic audiences, and society at large.