Llyn Mair is a beautiful, roadside lake surrounded by mixed woodlands. A variety of water birds may be seen, and water lilies are present in summer. The lake was created as part of a hydro-electric scheme for nearby Plas Tan y Bwlch. It is now a popular picnic place and a starting point for woodland walks. There is a small car park beside the lake, which is on the B4410, and it is only a short walk from Tan y Bwlch station on the Ffestiniog Railway.
