Wales' first copper works was established by a German, Ulrich Frosse, at Aberdulais Falls in 1536, making it one of the Principality's earliest industrial sites. After copper came iron smelting, then corn milling, and finally a tinplate works which remained in use until 1880. Now maintained by the National Trust, the buildings which remain are from the tin works. The water wheel - a more recent addition - is used to generate electricity.