REGNITZ, a river of Germany, and a left-bank tributary of the Main, the most important river of the province of Lower Bavaria. It is formed by the confluence, near Fürth, of the Rednitz and Pegnitz. The united river flows north through an undulating vine-clad country, past Erlangen, Baiersdorf and Forchheim, from which point it is navigable, and falls into the Main at Bischberg, just below Bamberg, after a course of 126 m. Near Bamberg it is joined by the Ludwigskanal, which, running parallel to it from Fürth and separated by the railway, forms the water-connexion between the Main and the Danube. Its main tributaries from the right are the Gründlach and the Wiesent, and from the left the Zenn, the Aurach and the Aisch.