Glaswaldsee

The Glaswaldsee near the spa town of Bad Rippoldsau-Schapbach in the Central Black Forest in Germany lies in a cirque that is sunk into the steep eastern mountainside of the Lettstädter Höhe. It is part of the nature reserve of the same name that was established in 1960.

The tarn formed in a cirque that was carved from the bunter sandstone rock out by a glacier during the ice age. Steep banks surround the lake which is up to 11 metres deep and has an area of about 3 hectares. Its diameter varies between 170 and 220 metres.

Source: Wikipedia