With green roofs, urban forestry and other developments, the City of Chicago is a leader in several aspects of big-city sustainability. One of its latest initiatives is Mayor Rahm Emanuel’s plan to create 800 new parks, including a “sky park” to replace an abandoned industrial rail line. The figures above from The Trust for Public Land / Michael Van Valkenburgh Associates, Inc. show the city’s vision for a $92 million, 2.7 mile sky trail known as the “Blooomingdale Trail”. Read more about it on Grist in a report from Chicago-based journalist Lori Rotenberk. If your city is interested in similar projects, the non-profit organization “Rails to Trails Conservancy” is an excellent resource.