Thanks to its storied (and widely used) public transportation, energy-efficient housing and good water quality, New York City ranks a place among the nation's green cities. Central Park makes it even greener. Considered a folly of epic proportions when its 843 swampy, muddy acres were set aside in the 1850s, Central Park is a wilderness within the urban core. More than 80 percent of NYC residents use public transportation, something that earns the city bragging rights.
New Yorkers burn gasoline at the rate the U.S. did in the 1920s. The key to the city's low use of fossil fuels, pesticides and other energy sources is population density.