rises to the south, only 1 km north of the source of the River Nagold at 822 m (in the parish of Besenfeld); the Kaltenbach rises to the northwest, on the southern slopes of the Schramberg at 907 m (in the parish of Forbach in the Murg valley). Great Enz and upper reaches in the Black Forest From the confluence of the Poppelbach and Kaltenbach, the Great Enz initially flows through a narrow wooded valley that, after a small change in gradient, opens into the much broader valley of the Rombach, joining from the west. The valleys of the Enz, Rombach and other western tributaries of the upper reaches are characterised by glacial cirques from the last ice age. After the Enz valley widens at Enzklösterle it narrows again until it reaches the next glacial valley, the Kegeltal, at Sprollenhaus. Having hitherto flowed northeast, the Great Enz swings northwards and flows through a steep valley that cuts across the mostly wooded bunter sandstone plateaux of the northern Black Forest. From the well-known Old Württemberg resort of Wildbad, the valley is densely populated. At Calmbach, where the Little Enz empties into the main river, follow the settlements of Höfen an der Enz and Neuenbürg. Here the Enz makes a wide loop enclosing a mountain spur atop which is Neuenbürg Castle. The Black Forest valley of the Enz has, including the valley of the Great Enz from Gompelscheuer, a length of approximately 38 kilometres and ends as it enters the Kraichgau region at Birkenfeld above Pforzheim. Enz valley in the Gäu and Neckar Basin After emerging from the Black Forest, the Enz flows down to its mouth in the Neckar Gäu country in the muschelkalk beds of the South German Scarplands. From a natural regional perspective, the Enz valley between Birkenfeld and Enzberg is counted as part of the Kraichgau, which continues to the north, further downstream it is part of the Neckar Basin between Stuttgart and Heilbronn. Overview of the tributaries Tributaries from the confluence of the Little (Kleine) and Great (Große) Enz. Tributary lengths are based on the source furthest from the mouth. Kleine Enz, from the right in Calmbach, 20 km and 88 km2. Förtelbach, from the right in Höfen an der Enz. Eyach, from the left between Höfen an der Enz and Neuenbürg, 18.5 km and 52.6 km2. Rotenbach, from the left in hamlet of Rotenbach near Neuenbürg.