NPRNTeitlMath O SaflePerthynasNPRN402080TeitlIronstone Levels, East of Plymouth Ironworks, Merthyr TydfilMath O Saflen/aPerthynasAssociated withNPRN34853TeitlPlymouth Ironworks: Railway Tunnel;Trevithick's Tunnel, Merthyr Tramroad, Merthyr TydfilMath O Saflen/aPerthynasAssociated with
