As a narrator describes the scene, we watch the whole Katzenjammer clan camping in the park of the title, a composite of several national parks in the western USA. There are several spot gags, including Mama taking a picture of a bear and ending up being photographed by several bears. Mama has a run-in with the law for picking a flower; The Captain has his own for feeding a bear, which turns out to be a ranger/cop in disguise. Also featured are the many geysers, where the boys fetch water for the radiator; it erupts, both there and in The Captain's belly after he drinks some.
—Jon Reeves <jreeves@imdb.com>