Its 18th-century ironworks, complete with blast furnaces, water balance tower, lift and workers’ cottages, are some of the best preserved in Europe.
Mae'r ffwrneisi adfeiliedig i'w gweld hyd heddiw gerllaw olion trawiadol y ffowndri, y tŷ cast a'r tŵr cydbwyso dŵr a godai wagenni i'r awyr i uchder o 80 troedfedd.