Konzertsegel, Open-air stage on the Lake Constance shore, Radolfzell, Germany

The Konzertsegel is a white tent-like roof structure along the Lake Constance waterfront that resembles a billowing sail. The open-air venue provides space for musical performances, markets, and community gatherings right by the water's edge.

The Konzertsegel was built in 1989 as the roof over the open-air stage on Radolfzell's redesigned lakeshore, where old embankments had been removed in the mid-1980s. Its cable-net structure covered with polycarbonate panels was the first of its kind and served as the prototype for the curved facade of the German Pavilion at Expo 1992 in Seville, later dismantled. It cost around 700,000 DM and has been a protected monument since September 2017.

The sail-shaped stage is used for the Fronleichnam procession, when one of the altars is set up beneath it. Since 2017 the Seefestival Radolfzell has taken place on and around the Konzertsegel. The structure is one of the town's landmarks, alongside the Münster.

The venue sits right on the lakeshore and is easy to reach on foot from the town center. It is best experienced during an event, when activities and crowds bring the space to life.

The sail was the first structure to combine a cable-net frame with polycarbonate panels, a technique later used for the German Pavilion at Expo 1992 in Seville. That pavilion was dismantled after the world's fair, leaving the Radolfzell prototype as the surviving example. The panels are replaced almost every year because they are deliberately damaged by stone throws.