Llyn Brianne: Highest Dam of this type in Europe
The dam, built with a clay core and rock fill, is believed to be the highest of its type in Europe.
Work started on the reservoir in October 1968, and the first water was supplied in October 1972. Princess Alexandra formally opened the reservoir in mid 1973
In the early 1990's Welsh Water decided to increase their investment to make Llyn Brianne produce economically viable amounts of hydro-electricity.