There are even reasons to think a civilization existed over 300 million years ago. Find All the Information You Need to Know About Ancient History of Earth and the USA.
Megaliths · Antediluvian Giants · Atlantis
A Timeline of Intelligent Life on Earth
Non-religious explanations and history. Stories. Dimension of Life explained. Good read. An explanation of what it was about, how it came together, what ancient mystery is about.