25-year-old 'South Park' 4th graders greet Denver International Airport travelers

Who better to greet visitors at Denver International Airport than 25-year-old 4th graders? That's just what's happening as "South Park" celebrates a quarter of a century of shows.

Cutouts of Stan, Kyle, Cartmann and Kenny were greeting travelers in the main Jeppesen Terminal this week as they come up from the underground trains. And fans were free to get their photos taken with the cartoons, or pose for a selfie.

Colorado is, of course, home to the fictional setting of the Comedy Central animated series. Creators Trey Parker and Matt Stone grew up here and met at the University of Colorado Boulder.

It's a partnership that's led not only to "South Park" but also the Broadway hit "The Book of Mormon."

First the focus was on celebrating those trouble-making elementary school students with a two-night concert run at Red Rocks Amphitheatre (where Parker and Stone joined Primus and Ween on the iconic stage. Members of Rush also made special appearances.)

Friday and Saturday, McGregor Square is hosting "South Park: The 25th Anniversary Experience." It's a travelling exhibit with props, artwork as well as never-before-seen scripts, storyboards and concept art.

It turns out the studios have a storage unit where many of them items have spent the last 25 years.

The exhibit is housed within a shipping container to make you feel as if you're stepping into that vault. You'll find a Cartmann-inspired paint job giving you chance for a very special selfie, all free.

Paramount is the parent company of both "South Park" and CBS News Colorado.