NPRNTeitlMath O SaflePerthynasNPRN403806TeitlElan Aqueduct: Knighton Tunnel Observation Tower East, Black HillMath O Saflen/aPerthynasAssociated withNPRN412105TeitlElan Aqueduct: Knighton Tunnel Observation Tower West, Black HillMath O Saflen/aPerthynasAssociated withNPRN95469TeitlElan Aqueduct, Elan Valley Water Scheme, Birmingham Corporation WaterworksMath O Saflen/aPerthynasPart of
