I watched a 1955 Czech film “A Journey To The Beginning Of Time”. I read that it was being rereleased in 4k at very high price, but managed to get hold of an old copy and downloaded some subtitles.
Directed by Karen Zeman, it is a good old Boy’s Own type of adventure. Four boys (the only actors in the film) row through a cave into prehistory and the further they go, the further back in time they go, through the great epochs of prehistory.
A very clever mix of live action, drawing, and stop-motion animation - influencing later artists like Ray Harryhausen - the boys encounter mammoths, sabre-toother tiger and various dinosaurs..