Thur

Thur is a river in northeastern Switzerland, a left-bank tributary of the Rhine and part of its drainage basin. It flows through the cantons of St. Gallen and Thurgau and has played a role in regional settlement, agriculture, and industry.

The river rises in the eastern Swiss Alps region near the border between St. Gallen and Appenzell Ausserrhoden and generally runs northward, passing through valleys in Toggenburg and the Thurgau plain before joining the Rhine downstream of Lake Constance.

The Thur's watershed covers a mix of agricultural land and small towns. The river provides irrigation water, supports limited hydropower, and hosts riparian habitats. In the 20th century, water quality improved after the construction of wastewater treatment facilities; ongoing river restoration aims to maintain biodiversity and flood protection.