A forest planted inside an Austrian soccer stadium opened to the public on Sunday with a message that one day nature might only be enjoyed in a museum-like environment.

Basel-based artist Klaus Littmann set up the forest of 300 trees in Klagenfurt's 30,000-capacity Woerthersee stadium for the "For Forest" exhibition that will run until 27 October.

While climate change has recently become a pressing political issue in much of the world, the idea for the exhibition is not new - Austrian artist Max Peintner created a drawing in the 1970s that would come to inspire Littmann's installation.

Peintner thought about industrialisation and its effect on nature, the Italian landscape artist who planted the forest, Enzo Enea, said.

"I see the problems in Asia, in China, how the cities are built without much green," he added. "People need nature."