Sydney's Festival of Dangerous Ideas is presenting Heap, an unusual installation in which 80 artworks by eight Australian artists are buried under tonnes of dirt in the foyer of Carriageworks, inviting the public to physically dig them up. The project blends exhibition, installation and mock archaeological dig, with each hidden piece representing a "dangerous idea" that organisers hope will prompt reflection on issues such as climate change, colonisation and labour rights, using Australia's mining history as a deliberate metaphor.

Among the buried works are a bronze mushroom, a canister of kangaroo apple, a spider costume, a human figure cast in hardened dirt, and 25 tiles bearing a labour agreement between artist Sophie Penkethman-Young and the 3D printer she used to make them, all interred beneath around 120 tonnes of earth. Visitors who unearth pieces this weekend must hand them over for display rather than keep them, and festival director Danielle Harvey said art offers a fresh way to draw attention to difficult conversations. Wiradjuri artist Brook Andrew also contributed a series of canisters containing medicinal and edible plants as part of the buried collection.