Knick-Ei ("dented egg") was the nickname of a sports hall located at the corner of Feldstraße and Bahnhofstraße in the city of Halstenbek, located in Pinneberg county in the state of Schleswig-Holstein in northern Germany. The nickname refers to the hall's dome-shaped roof which collapsed twice during construction. The building's official name was "Sporthalle Feldstraße".
Read more about Knick-Ei: Design, Planning and Construction, 1997: The First Collapse, 1998: The Second Collapse, Legal Proceedings, Petitions and The Attempt To Rebuild The Dome, Demolition, Compensation and Total Cost, Media Coverage