OSM tag name=Llyn y Gadair matches Llyn y Gadair in these Wikidata fields:
OSM tag name:cy=Llyn y Gadair matches Llyn y Gadair in these Wikidata fields:
OSM tag name=Llyn y Gadair matches Llyn y Gadair, Rhyd Ddu in these Wikidata fields:
OSM tag name:cy=Llyn y Gadair matches Llyn y Gadair, Rhyd Ddu in these Wikidata fields: