TED Radio Hour
Thu, 09/20/2012 - 1:00pm
Thu, 09/20/2012 - 7:00pm

For centuries, cities have been bringing people together. For the first time in history, more than half the world's population lives in cities. What draws people to them? What changes when we live closer together? We investigate the future of our urban zones, and what cities offer humanity toward a sustainable future.