An innovative approach to agriculture in urban centers, where space is at a premium, is explored: vertical farming. That means turning the rooftops of buildings into "farmland" and the buildings themselves—or parts of them—into greenhouses. Included: agricultural towers in Singapore; and, in the Netherlands, the use of LED lights to replicate sunlight during the winter months.
Modern cities that have been created from scratch in South Korea, China and Saudi Arabia are examined. They're energy efficient and run by computer. Many see the cities as urban models that should be replicated elsewhere; others, however, see them as soulless enterprises that foreshadow an Orwellian future.