At a height of 1,238’, Llyn Llagi is a good hike to get there, but well worth the effort with wild Brown Trout of ¾ lb regularly caught. A lot of the lake is quite shallow, so the likeliest parts are to be found are below the steep cliffs, where the water is much deeper, however care must be taken when fishing in this area.

It is approx 8 acres and about two and a half hours walk from Tanygrisiau. It can also be reached from the Nant-Mor valley side in about 45 minutes.