Plas Y Brenin 3 August 2022 / Plas Y Brenin Enjoy the fresh, clean waters of Llynnau Mymbyr, and Plas y Brenin’s supervised Open Water Swimming sessions, all with the spectacular backdrop of the Snowdon Horseshoe._x000D__x000D_ _x000D__x000D_ pyb.co.uk/open-water-swimming