La Ciudad de las Ideas (CDI) is a conference created by Andrés Roemer, to empower citizens and present innovative ideas in science, technology, art, design, politics, education, culture, business, entertainment and other areas of knowledge. CDI created a 21-minute format to encourage debate. Daniel Dennett called it the "brain Olympics". Since 2008, up to 3,600 attendees have gathered every November in the center of Puebla. The festival has been promoted in Azteca Trece and Proyecto 40 and on the event's website, social media, and through a science bookstore located at the festival site.