A ramshackle wooden tower consisting of doors and windows from Qing Dynasty buildings collapsed Wednesday, just after a thunderstorm at the Documenta art show in the German city of Kassel, according to dpa. The 12-metre-high work, entitled Template, by Chinese artist Ai Weiwei, comprised leftovers from buildings ripped down during a building boom in China. It was intended as an elegy to China's rapidly vanishing past. Organizers of Documenta, which began on Saturday, said the wooden tower would be erected again on its site in a courtyard of the expo's Aue Pavilion. Ai has attracted international attention with Fairytale, a performance art entry in the expo, which is held in Kassel every five years and runs until September. Fairytale requires the presence of 1,001 Chinese visitors, who are staying in a former factory, and 1,001 carver chairs, all between 100 and 400 years old. The blackened Chinese chairs are available all over the exhibition for art-lovers to rest in.