It is definitely possible that the cycle has been going on for a long time. The abandoned and buried city of Gobekli Tepe was discovered in 1994 and carbon dating shows it was created at least about 10,000 BC. This was not supposed to be possible, according to the mainstream theory on human development. The structure is massive and in very great shape because they buried the city after abandoning it. They still don't know how big it is, but it has megalithic stones that are a mystery.

https://www.gaia.com/article/what-is-gobekli-tepe