A black lake on the edge of the Jiráské rocks

On the edge of the Jiráské rocks, which belong to the NPR Adršpašsko-teplické skály, there is an artificially created Black Lake. The epithet Černá caught on until it eventually became the official name. The dark color of the lake is caused by substances released from peat, mosses and a thick layer of plant residues in the mud. The mentioned composition also causes considerable acidity of the water, pH 4,7.
Because the lake is located under the rocks in…