Hydrogen Valleys—regional ecosystems that integrate green hydrogen production, storage, distribution, and end-use—are emerging as key enablers of the European decarbonization agenda. Positioned at the intersection of energy, industry, and mobility systems, they embody sustainability-oriented innovation (SOI) by embedding environmental objectives into technological deployment, fostering multi-stakeholder collaboration, and promoting circular economy principles. Despite rapid policy and investment momentum, there is limited research that applies the multi-level perspective (MLP) framework to understand how Hydrogen Valleys evolve as systemic innovation niches capable of influencing regimen and landscape dynamics. This study introduces a novel dual-lens analytical framework that integrates SOI and MLP to assess Hydrogen Valleys not merely as technical pilots, but as sociotechnical experiments embedded in systemic transformation. By merging these frameworks, we develop a typology that distinguishes between Pilot, Transitional, and Systemic valleys across governance, circularity, digitalization, and regimen integration. The analysis reveals that Hydrogen Valleys operationalize SOI by linking diverse sectors, testing novel business models, and enabling localized hydrogen value chains. From an MLP lens, they emerge as niche innovations that increasingly interact with incumbent energy regimens under pressures from climate targets, energy security needs, and technological competition. Key success factors include stable policy roadmaps, demand-side commitments, and integrated infrastructure planning. However, major barriers remain in achieving cost reduction, regulatory harmonization, and skills development. The findings highlight that coherent policy support, social sustainability integration, and international collaboration— particularly under initiatives such as the Clean Hydrogen Mission—are critical for scaling their impact. This research contributes a theoretically grounded framework for understanding Hydrogen Valleys as catalysts in Europe’s green transition, offering actionable insights for policymakers, industry leaders, and researchers.