CN City (also known by fans as Toon City, Downtown, The City of Cartoon Network, and the Cartoon Network Universe) was the third era of Cartoon Network. It began on June 14, 2004, replacing Powerhouse, and was the main branding image of the network from that point until April 9, 2006, when it became a secondary brand in favor of Yes! (which began on April 3, 2006).

The era was named for its bumpers, which were set in a CGI city and featured CN characters interacting with one another. These bumpers were produced by Animal Logic. The City era is notable for the new logo it brought with it, as well as the female announcer and the slogan "This is Cartoon Network."