This 141 km (88 mi)[1] long river is a left tributary of the Lech.

The Wertach originates in the Northern Limestone Alps in Bad Hindelang, east of Sonthofen (district Oberallgäu).

It flows north along the towns Wertach, Nesselwang, Marktoberdorf, Kaufbeuren, Schwabmünchen and Bobingen.

The Wertach flows into the Lech (itself a tributary of the Danube) in Augsburg, and has a deep reservoir with a hydroelectric power plant.

This article related to a river in Bavaria is a stub.