The newly renovated and opened technical monument - the portal of Josef Mining Gallery - can be found nearby Černá v Pošumaví near the municipality of Mokrá. It can be accessed via the new gravel nature trail leading to it.
For several decades, the territory around Černá v Pošumaví was a significant producer of graphite.
As water accessed the mining galleries, drainage tunnels began to be driven - Josef Gallery of 1897 is exactly the case. The total length of this tunnel measured over 2 kilometres. A stone portal is installed at the heading; decorated by a prince coronet, it is located near the settlement of Mokrá in the forest section, not far away from the so-called Little Lipno.
Since currently, Josef Gallery and other relics of mining work near Mokrá are the best-preserved mining monuments from the period of mining South Bohemian graphite, this technical monument should in no case be missed. An extra attraction certainly involves the fact that there is a small cup available on the gate of the tunnel; it can be used to scoop the local water of very good quality which flows through the canal.