An Austrian football stadium has been transformed into a native central European forest.
Designed by Klaus Littmann, the installation is a statement against climate change and deforestation.
Hosting almost 300 trees, the stadium hopes to attract wildlife during the seven weeks the installation is open.
It was inspired by a dystopian image of a world where nature could only be seen in designated spaces, like animals in zoos.
Littman stumbled on the drawing in 1970. It was called The Unending Attraction of Nature by Max Peintner.
"I thought that the idea behind the work was simply fascinating," Littman told the BBC. He said he wanted to purchase the drawing but it had already been sold to an American art collection.
"That's when I decided I wanted to realise the drawing, have it in front of me and experience it in real life," he said.
Three decades later, the installation, which has been named For Forest - The Unending Attraction of Nature- has opened its doors.
Both artists worked around a vision of natural spaces only existing as objects in an exhibition.
Planted inside Wörthersee Football Stadium in Klagenfurt, which can hold up to 30,000 spectators, the forest is expected to change colour as autumn approaches.
The 299 trees were all brought in from nurseries and will live on after the project in a planting site near to the stadium, causing as little interference to nature as possible.
"I have never worked with living beings before and I am absolutely aware that this cannot be compared to working with a sculpture, a photo or a painting," said Littman. "The work has to be adapted to the species and has to be done with a lot of attention and respect. "
He worked alongside Enzo Enea, a landscape architect, who had lots of experience working with trees in different environments, to ensure they were properly cared for.
"Perception is really a central theme in my projects," he said. "In For Forest, I do so by taking something which we know in our everyday life and putting it in a new context. This forces people to question things that surround them and that they take for granted, in this case trees."
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