the Sauer from the North Vosges joins the Rhine almost opposite the Murg. Waterbody data From the confluence of its two headstreams (Rechtmurg and Rotmurg) in Baiersbronn-Obertal to its mouth on the Rhine the Murg is 72.350 km (~ 72.4 km) long. Together with the Rotmurg which rises at the Rotmurgbrunnen near Ruhestein it is 79.661 km (~ 79.7 km) long and together with the Rechtmurg which begins on the Schliffkopf at the Murgursprung and has a length of 7.881 km it is 80.231 km (~ 80.2 km) long. The catchment of the Murg covers 617 km2. In relation to its catchment the Murg has a high volumetric flow (18.4 m³/s). The catchment areas of the Murg headstreams and its tributary, the Schönmünzach, have an area flow rate of 50 L/s.km2, the highest in Baden-Württemberg. Natural regions The Murg flows from south to north through four very different valley landscapes. Its upper section in the area of Baiersbronn is a typical Black Forest valley with broad meadow bottoms and villages once dominated by agriculture. Many of the side valleys have a typical trough valley shape with steep sides. The middle section of the Murg valley is a lonely, forest gorge with granite crags and a gradient of up to 3.3%, very much like a mountain stream. Until 1918, the Murg, together with the Raumünzach, its biggest tributary, a well known whitewater river due to its weight of water. Since then, the hydroelectric potential of the river has been used in the Murg Power Station. It lies just above Forbach, the main settlement in this part of the valley. The lower Murg valley is, like the Wiesental, one of the industrial corridors of the Black Forest. The valley here is over 700 metres deep, initially with a trackless gorge bottom that increasingly broadens and provides room for a settlement strip of numerous villages and towns. Its historic centre is Gernsbach, also the hub of the paper and cardboard industry of the valley; the largest town has become Gaggenau with its tradition-rich motor manufacturing (including Unimog). The river is accompanied in many places by industrial ditches and from Gernsbach-Nord has been almost entirely canalised. Renaturalisation work was carried out at Bischweier in 2011. The aim was to create a near-natural riverbed with differences in current, substrates and depth, so that a variety of habitats could be created for fish and other small