Perlenbach

It originates at Schönwald-Reichenbach from the two streams Lohbach / Hraniční potok and Lauterbach near the Czech border (50° 12′ 57″ N, 12° 9′ 40″ O, approx. 635 m above sea level), as well as from the Stockbach, which begins its course at the eastern outskirts of Schönwald. The Perlenbach Valley runs northwest to Rehau, where the Perlenbach and Höllbach merge into the Schwesnitz. Other smaller tributaries include Hussitenbächlein, Mähringsbach, Bocksbach, and Potrasbach.

In 1412, the stream was referred to as "Gryna" and later as "Grünau". It got its name from the originally rich occurrence of the freshwater pearl mussel. There is a legend about a pearl discovery related to the name change. Between 1733 and 1952, mussels were fished and pearls sought there by officially appointed "pearl inspectors" based at the "Pearl House". This was initially a margravial and later a royal Bavarian privilege. Today, the pearl mussel is nearly extinct there as well.

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