OSM tag name=Llyn y Dywarchen matches Llyn y Dywarchen in these Wikidata fields:
OSM tag name=Llyn y Dywarchen matches Llyn y Dywarchen, Rhyd Ddu in these Wikidata fields:
OSM tag name=Llyn y Dywarchen matches Llyn y Dywarchen, Wales in these Wikidata fields: