Cherry Creek is a real-life neighborhood in Denver, Colorado. It made its only physical appearance in the Season Four episode "The Tooth Fairy Tats 2000", where it is described as "the wealthiest neighborhood in Colorado".
Background
In "The Tooth Fairy Tats 2000", The Boys come up with a plan to steal a tooth from a Rich Kid in Cherry Creek, due to Cherry Creek being extremely wealthy and giving them an opportunity to obtain a lot of money. When they arrive, Stan and Kyle hold Cartman on a pole, who is dressed as the Tooth Fairy, in order to steal the kid's tooth. However, it turns out that another group of boys is doing the same thing. The two groups end up arguing and waking up the rich kid, who is told to shut up.
In "Here Comes the Neighborhood", when Token and his family are shopping through J-Mart, Sharon Marsh states that they are rich enough to be able to afford shopping at Cherry Creek.