Wehr, Heritage weir in Landsberg am Lech, Germany

The Karolinenwehr is a four-step overflow weir on the Lech just below the old town of Landsberg am Lech. On its right bank the Mühlbach is diverted, a channel that once drove mills and now generates electricity. The historic cascade form has been kept through repeated rebuilds, most recently between 1993 and 1996.

The weir existed by 1364 at the latest, when it was built as a single-step dam to regulate flooding on the Lech. Floods damaged it repeatedly, and additional steps were added in the 18th, 19th and 20th centuries. To its right, the Mühlbach was diverted to drive mills, and it now generates electricity. The weir was rebuilt several times while keeping its historic cascade form, most recently between 1993 and 1996.

The weir's name recalls the rafting era: boats and rafts bypassed it via the wooden "Lange Fahrt" track, paying a toll to be hauled around the barrier. After rafting declined in the 20th century, that track was demolished in the 1970s to make way for the Inselbad. The Mühlbach canal, diverted to the right of the weir, once drove mills and now generates electricity.

The weir sits just below the old town, and the Karolinenbrücke directly above it is one of three main routes into the Landsberg centre, with two lanes and footpaths across the Lech. The Vater Lech sculpture stands on the bridge's west side.

Rafts once bypassed the weir on a wooden track called the "Lange Fahrt", paying a fee to be hauled around it. After rafting declined in the 20th century, the track was demolished in the 1970s to make way for the expansion of the Inselbad. The Karolinenbrücke just upstream carries two lanes and footpaths over the Lech, and on its west side stands a sculpture of Vater Lech.