Video has closed captioning. At the Concurs de Castells competition in Catalonia, Spain, teams battle the force of gravity as they compete to build the tallest, most complex human towers. Hundreds of people come together and form a giant circle, called the pinya, to support the towers up to 10 people high. But it’s the lightest members of the team children who get sent to the very top. Aired: 09/13/16