The Afon Fachwen (?little white river?) gathers its waters from Elidir Fawr and flows into Llyn Padarn just 150 metres below the Cae Mabon boundary. Once there was a trout fishing lake higher up the hill where the fishing rights were held exclusively by the managers of the Dinorwic Slate Quarry.

But one year (in the 1950s) there was a terrific storm and the lake became dangerously full. That night the lake-keeper was not in his nearby cottage (was he drunk or dead, no-one knows) and therefore did not open the sluice gates to relieve the pressure.

Eventually the dam burst and water hurtled down the hillside, scattering boulders everywhere. The course of the river was changed forever. But next morning the quarrymen?s wives filled their baskets with fish plucked from the path of the torrent and that night ate one final fish supper!

Since then it?s been rare to see brown trout in the river pools. But the lake itself (Llyn Padarn) contains trout and, in its deeper recesses, Arctic char, trapped there since the Ice Age.

Migrating salmon are sometimes seen from the old bridge at the foot of the lake as they make their way back to their spawning grounds. The round-the-lake footpath is 5 miles and takes about 2 hours to walk.