Built from curvaceous expanses of wrought iron and designed to house the Jubilee Exhibition of 1891, Výstaviště played a key role in Prague's art nouveau movement. During the late 1940s, the building served as the site of various communist congresses, but it's now mainly used for trade shows for industries that range from information technology to pornography.
In early 2009, the main hall collapsed at one end. For the time being, you'll be deprived of the interior's vivid stained glass and floral decorations, but the fairgrounds are still worth a visit if you're not troubled by the pounding pop music on the loudspeakers. The best view of what remains of the main hall's exterior is from the back, where a monumental modern fountain gushes kitschily at night in time to popular classics and accompanied by a light show. Nearby sit architectural oddities such as the Lapidárium and the delightfully dilapidated funfair Lunapark, which pulls in weekend crowds of Czech families.