The Opera Leśna (Forest Opera) is one of the oldest and largest open air theatres in Poland. The theatre is located in the forest of Sopot, between the cities Gdansk and Gdynia at the Baltic Sea.
In 2010 the roof structure for the stage and stands has been replaced by a lightweight translucent PTFE/glass membrane with an area of more than 5,000 m².
This large PTFE canopy provides weather protection to the attendees to the performances: the canopy is supported by a large central arch structure. Cables are connected to this arch and to the perimeter steel columns, while the columns are stabilized by tie-back cables. Edge cables span between the columns to support the edge of the membrane panels. The membrane cladding is connected to the cables and steel arch and membrane closures are added to provide a weatherproof system.