Journey to the Beginning of Time

The story involves four teenage friends who take a rowboat along a "river of time" that flows into a mysterious cave and emerges on the other side onto a strange, primeval landscape. The boy actors were Josef Lukáš (Petr, the main narrator), Petr Herrmann (Toník, who also narrates in part), Zdeněk Husták (Jenda), and Vladimír Bejval (Jirka). As they make their way upstream, they realise that they are travelling progressively farther back in time, and face various perils as they do so (but learn much about prehistoric life in the process). The animals depicted in Cesta do pravěku were never shown interacting with animals of other periods and it is assumed that different parts of the river represented distinct time periods. The plot is somewhat similar to that of the novel Plutonia (1915) by the Russian palaeontologist Vladimir Obruchev, in which a team of Russian explorers enter the Earth's crust via an Arctic portal (a huge depression in the Earth surface created many millions of years previously by the impact of a giant asteroid, into which prehistoric animals had entered), and follow a river that leads them through a sequence of past geological eras and associated animal life. Some scenes in Cesta do pravěku recall Arthur Conan Doyle's 1912 novel The Lost World, with four male protagonists exploring a prehistoric world where they find evidence of native human habitation, are attacked by a group of enraged pterosaurs, witness a twilight fight between a carnivorous dinosaur and a herbivorous one, encounter a Stegosaurus up-close, and see one of their members, Petr, nearly chased down by a Phorusrhacos.

Zeman's use of unorthodox and seamless production techniques ensured that the film was free of jerky stop-motion sequences and grainy splicing of stop-motion with real-time footage that characterised Hollywood's animated films until the advent of computer-generated imagery. Filming took place on the Morava river near Bzenec town in the Czech Republic at the nature reserve named (in Czech) Osypané břehy and on studio sets.

Zeman was heavily influenced by the palaeo-art of the celebrated Czech artist Zdeněk Burian (1905-1981), and much of the film's imagery was inspired by Burian reconstructions that had been painted under the guidance of Czech palaeontologist Josef Augusta (1903-1968). In some scenes, 2-D 'profile' images of animals originally depicted by Burian were filmed in real time (as in the Styracosaurus sequences), whilst other well-known Burian scenes were recreated in stop-motion using a combination of 2-D and 3-D models (as in the Deinotherium and Uintatherium sequences). Possibly for the sake of continuity, Zeman also used models or 2-D profiles when depicting extant species including bison, a python, flamingos, vultures, various antelopes, giraffes, and a jaguar (which was briefly spliced with footage of a real animal in one of only three instances of live species footage). In some scenes, miniature models of the actors and their boat/raft were also animated.

In addition to numerous miniature animal models and 2-D 'profiles', Zeman also used larger models of heads and bodies of animals (including a full-size 'dead' Stegosaurus and swimming woolly rhino, Brontosaurus and Trachodon models), as well as life-sized model plants (as in the Carboniferous forest sequence, and the encounter with the Styracosaurus). The use of 2-D profiles and 3-D models animated by concealed means had the advantage of filming in real time without the need for labour-intensive stop-motion. Two of the film's prehistoric species were not based on Burian images; the Stegosaurus and the Ceratosaurus with which it fights in a twilight scene (it remains unclear as to why Zeman did not use Burian images in these instances).

Cesta do pravěku was made on what would be considered a small budget by western film-makers. It discussed the various time epochs as defined by palaeontologists and the types of animals typical of those periods, using information known in the 1950s. Whilst many animated feature films, particularly those in the US, used models of prehistoric animals in contrived sequences, Zeman instead depicted animals acting naturally in their own environments as if being filmed for a documentary, with the actors observing from the relative safety of the river. Such a philosophy was unusual at the time and was more typical of later TV productions that depicted prehistoric animals in an educational context (including the BBC's Walking with Dinosaurs and Walking with Beasts series) which became popular following the advent of computer-generated imagery that negated the need for time-consuming, highly skilled manual animation. The original release of Zeman's film was 93 minutes, although the East German release had a slightly shorter running time.

In 1966, another version of the film was released in the US by William Cayton whose company had been marketing Russian animated cartoons and feature films from the 1940s and 1950s, especially those of the famous Soyuzmultfilm studios (well known titles included The Firebird, The Frog Prince, Beauty & the Beast, The Space Explorers, and The Twelve Months). The films were dubbed, sometimes re-titled, partitioned into chapters and distributed to US TV stations. In the case of Cesta do pravěku, Cayton replaced the opening and closing scenes of the original with new footage of American boys who entered the film in a dream sequence whilst visiting the American Museum of Natural History in New York. The film was copied to poor quality film stock and edited into short segments (about six minutes each) for presentation as a serial, syndicated to various children's television programs. The US version was released on VHS video by Goodtimes in 1994. Because of the new sequences, none of the actors' faces could be shown until the original footage began.

In April 2001, Cesta do pravěku was screened at the Brooklyn Academy of Music in Brooklyn, New York, as part of the retrospective entitled The Fabulous World of Karel Zeman. In 2010, it featured at the 50th Zlín Film Festival (May 30 - June 6) in the Czech Republic, one day of which (June 4) was dedicated to Karel Zeman to honour the centenary of his birth. The four original actors also attended the ceremonies (three from the Czech Republic and one - Vladimír Bejval - from the US).

In 2004, a DVD version of the film appeared in Japan, in Germany in 2005, and Spain in 2007. The Japanese and Spanish versions had different digital masters. The first German DVD had no digitally remastered images, but another German version with Czech and German dialogue, and 15 min of extras showing some of Zeman's filming techniques, was released in Jan 2010. This version used some modified sound effects for the dubbing, and the picture quality is below that of the original. Unfortunately the announced DVD of the original was held back for licence-juridical reasons and it remained unavailable commercially (as of April 2011) although copies of the original circulate amongst enthusiasts. In February 2020, The Criterion Collection included the film as part of their "Three Fantastic Journeys by Karel Zeman" box set.

Several scenes of the film were used by the British ABC (Associated British Corporation) in the 1961 television serial Pathfinders to Venus. The scenes were that of the Pteranodons flying overhead and the battle between the Ceratosaurus and the Stegosaurus.

• List of stop-motion films

• Cesta do praveku at IMDb