The drift barrier is a result of the once economically important timber rafting in Passau, which began around 1729. In 1788 the first drift regulations were issued in Passau. At that time, the trip on the Ilz from the Bavarian Forest to Passau took around six weeks. From 1827 to 1831, the 115.5 meter long, 3.2 meter wide and 2.3 meter high Triftsperre tunnel was built near Hals, through which the drift water was directed from then on. This tunnel significantly shortened the longer route through the Halser river loop, with which up to 100,000 cubic meters of wood could be transported annually.

Since 1920, the weir of a power station has been damming the water of the Ilz at the Hals reservoir. The drift itself only came to a standstill after the end of the Second World War due to the continuous expansion of the forest roads.
A long wooden footbridge connects the Triftsperre to the Gasthof Zur Triftsperre.

Source: RegioWiki