Suhre

The river Suhre is a 34 kilometer long tributary of the river Aare in the Swiss cantons of Lucerne and Aargau. The river rises in Sempachersee (or Lake Sempach) at an altitude of 504 meters above sea level, and joins the Aare east of the town Aarau at an altitude of 362 meters. The most important side valley is the Ruedertal, which joins the Suhretal (or Suhre Valley) at Schöftland.

In medieval age, the river had several different names: Suron (1036), Suranum flumen (1210), Sure (1241). Today, the name is written without „h“ in the canton of Lucerne, and with „h“ in the canton of Aargau. The most important tributaries are the Ruederchen joining at Schöftland, the Ürke joining at Unterentfelden and the Wyna joining at Suhr.

The Suhre rises from the Sempachersee in Oberkirch (LU) north of the lake just next to medieval town of Sursee, which it traveres afterwards. After the underpass of the A2 motorway the creek Ron from the Mauesee joins the Suhre in the Sursiwald from the west (forest; left, Sursee). Chommlibach joins the Suhre right afterwards (right, Sursee). Then it runs further north between the villages Knutwil and Büron in the distance. Then it continues west of Triengen and east of the village Winikon in the middle of the valley and the last one in canton of Lucerne passing in the distance of the now Aargovian villages (Winikon, Reitnau, Attelwil, Moosleerau, Kirchleerau) situated at the bottom of the enclosing hills (about 650m to 850m a.s.l.) on each side of the flat, about 2 km wide valley. Just before Staffelbach, the Suhre traverses at 471m the end moraine (up to 519m a.s.l.) of the glacier that formed the upper Suhre Valley and flows then through Staffelbach.

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Wikipedia