Examples include the Knoxville Urban Wilderness in Knoxville, TN,[1] Purgatory Creek Natural Area in San Marcos, TX,[3] the Danube-Auen National Park in Vienna and Lower Austria,[2] the Turkey Mountain Urban Wilderness Area in Tulsa, and the Milwaukee River Greenway in Milwaukee, WI.
Jacob Riis and other reformers fought for parks in urban areas.
[5] While many societies had traditions of intense urban plantings, such as the rooftops of pre-conquistador Mexico City, these traditions did not reemerge on a larger scale in the industrialized world until the creation of naturalistic urban parks, such as the ones by Calvert Vaux[6] and Frederick Law Olmsted.
[7] More recently, groups such as squatters and Reclaim The Streets have performed guerrilla plantings, worked in and on abandoned buildings, and torn holes in highway asphalt to fill with soil and flowers.
[8] These actions have been effective in creating new planted zones in economically stagnant areas like urban Eastern Germany, where abandoned buildings have been reverted to forest-like conditions.