Vienna cemetery offers a 'return to nature' Vienna's Kahlenberg Cemetery was once a space reserved for the nation's rich and famous, but since October it is dedicating itself to so-called natural burials available to the general public. This ritual which involves being buried in a biodegradable urn at the foot of a tree after cremation is increasingly popular in Vienna. 'The urns and the ashes become part of nature,' says Peter Schauer managing Director of the cremation company Danubia, 'You nourish the tree, you become a part of the circle of life again.'