Llyn Eiddiw mawr is a large lake of about 22 acres area in the Rhinog mountains. It lies at a height of 1148 feet above sea level and has two small islets. Some old manganese workings can be seen towards the north-western corner. The nearest parking is on the verge at the end of a lane from Glan-y-wern at Grid Ref : SH629342, in front of the gateway - the track to the right leading up to the lake. Note that this lane has hairpin bends and some very steep gradients. If you have a long vehicle or a trailer, don't even think about it!
