The roof of the National Stadium in Warsaw, designed by GMP Architekten, is conceived as a lightweight structural system spanning a large-scale public interior. The roof is suspended from a peripheral steel cable net and stabilized by freestanding columns with inclined tie rods, allowing the stadium bowl to remain visually open and free of internal supports. At the center of the structure, a retractable textile membrane is integrated into the cable system. When deployed, it provides weather prot