Muerz, River, Styria, northeastern tributary of the Mur, River (Mura), 98 km long. The name is derived from Slavic "Muorica" (small Mura). The sources of the two headwater streams, Stille Muerz (Lower Austria) and Kalte Muerz, are north of Schneealpe mountain. The upper S-shaped Muerz Valley begins north of Frein an der Muerz (864 m), breaking through the Limestone Alps, separating Schneealpe mountain (Windberg, 1,903 m) from Veitsch mountain (Hohe Veitsch, 1,981 m). Upstream beyond Muerzsteg (782 m) the Muerz Valley is called Scheiterboden. The upper course of the Muerz (good water quality, class 1-2) passes Neuberg an der Muerz (730 m) and Kapellen (703 m). At Muerzzuschlag (670 m) the valley becomes wider. The defile at Wartbergkogel hill (717 m) divides the lower Muerz Valley in a higher basin around Krieglach (608 m) and in a lower one around St. Marein (537 m). At Kapfenberg-Diemlach control station, average rate of flow of 20,2 m3/second. The Muerz flows into the River Mur at Bruck an der Mur (491 m). The Southern Railway Line and the road connection Vienna - Styria - Carinthia, which is a Schnellstrasse (rapid transit route), run through the lower Muerz Valley.