Journey to the Beginning of Time (1955) review

Inquisitive Petr (Josef Lukáš) and his goody-goody pals Jirka (Vladimír Bejval), Toník (Petr Herrmann) and Jenda (Zdeněk Husták) want to know what prehistoric times were like, so they take a small boat through a mysterious cave and travel to the distant past, where they find a wooly mammoth, ancient weapons, animal paintings and several dinosaurs, including the stegosaurus and brontosaurus (among others).  It's basically an "educational" movie and strictly for kids with an interest in extinct creatures that once took up space on the surface of Earth (and are currently decomposing beneath it), and Zeman's use of stop-motion animation, special effects and puppets was considered groundbreaking in the mid-1950's.  Unfortunately, it's more of a "look and see" project instead of a "true" action/adventure tale: the boys glance around, notice strange things and make extensive notes in their logbook ... and there's little genuine risk of danger for any of them (with maybe the exception of that jaguar in the tree).