Ok. Erich Von Daniken was prone to wild speculation and telling fairy tales but stories of visitors from the sky go back thousands of years.
Ancient Astronauts - General
The sighting of strange objects in the sky may actually predate the emergence of modern man. Perhaps the earliest depiction of cylindrical objects resembling spacecraft, with what might be their extraterrestrial occupants, are those carved on a granite mountain and on rocks on an island in Hunan Province, China. They have been assigned a tentative age of 47,000 years, which puts them within the time-span of Neanderthal man, predating modern Homo sapiens.
We exist. That is beyond dispute. According to what we know about life and how it evolves the spontaneous creation of complex molecules appears to be inevitable under the right circumstances. It is built into matter itself and we know there are billions of earth-like planets within our galaxy. Life has had billions of years to evolve on myriad worlds so many alien travellers could have visited our world.
In Australia there are many rock paintings of lights in the sky. Aboriginals have told me they have dream time stories about these enigmatic objects which go back tens of thousands of years. Perhaps we are a novelty to the neighbours. A safari park of sorts.