Von Daniken wasn't right, but he did gather (I think for the first time in a popular title) descriptions of a lot of odd sites. At an early age he traveled with his family to Egypt. Helps to be born with a silver spoon.
Is such a thing even possible? Yes, it is.
Can’t say for certain if he was right, wrong, or perhaps a bit of both. How does one explain the Nazca Lines and other geoglyphs? Easy enough to make simple straight lines long in length in sand and gravel, but intricate depictions? How others quarried, transported and arranged enormous stones has never been discovered, and in many parts of the world where travel and transport is not simple or easy. Perhaps our ancestors had secrets for moving enormous weights that our shining scientists of today can’t explain, and they did it without help or maybe not. It’s what mysteries do, they make us wonder and I think that’s a good thing.