During Theme 1—“Integrating Knowledge Systems, with a focus on responsibility and respect for the ocean”—at the One Ocean Science Congress in Nice (June 4–6, 2025), the International Committee on Underwater Cultural Heritage (ICUCH) of ICOMOS participated in the “Human rights” session (Session ID 51397) . This session emphasized the recognition of both human and non-human rights to a healthy ocean, and the vital importance of including intangible and tangible underwater cultural heritage in ocean governance frameworks. ICUCH’s contribution spotlighted how underwater sites carry human stories, cultural identities, and sometimes even serve as memorials. By framing these sites within a rights-based approach to ocean stewardship, ICUCH argued they must be protected not only as environmental resources but also as living cultural legacies. Their intervention called for integration of heritage values into policy and science to ensure respect for community memory, ethical governance, and the rights of future generations.