Urban Facts

In 2012, China announced plans for "Great City," a car-free satellite city near Chengdu for 80,000 people. It would use 48% less energy, 58% less water, and produce 89% less waste than a conventional city. Like many of China's ambitious eco-city proposals, it never got built.

Seattle's Beacon Food Forest, which opened in 2012, spans seven acres and is filled with hundreds of edible plants including fruit trees, berry bushes, vegetables, and herbs. It's free and open to anyone who wants to harvest food, making it the first public food forest in an urban area in the United States.

Kowloon Walled City crammed 33,000 people into just 6.4 acres - one city block. That made it the densest place in recorded human history. About 300 towers rose 14 storeys high, packed so close that sunlight never reached the alleys. Neither Britain nor China governed it, so residents built their own unlicensed economy. It was demolished in 1993-1994. The site is now a park.