The Upper Lake is the more dramatic of Glendalough's two lakes — longer, deeper, and backed by steep glaciated cliffs that drop almost sheer into the water. The path from the lower enclosure along the lakeshore takes about 20 minutes and passes St Saviour's Priory on the way. The lake itself is a natural swimming spot in summer; the water is cold but clean and clear.
St Kevin's Bed — the cave above the south shore where the saint allegedly lived as a hermit — can be seen from the lake path and from the water, high in the cliff face. It's not safely accessible without ropes, which is rather the point. The combination of the still dark water, the cliff face rising behind it, and the ruins strung along the valley makes the upper lake the most atmospheric spot in Glendalough.