The boys go ziplining on their Spring break trip to the Rockies on South Park. "I Should Have Never Gone Ziplining" is the 6th episode of the 16th season.
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South Park Season 16 Episode 6 Quotes

Cold sore is what girls call it, Kenny. It's actually herpes.

Cartman

For four elementary school boys, an ordinary day becomes a descent into madness on "I Should Have Never Gone Ziplining."

Narrator