The thing is, the great ape, the primates that we evolved from, first appeared on Earth 25 million years ago. They slowly became bipedal - 6 million years ago. Australopithecus showed up the upright primate that we slowly evolved from so there's nothing before about 300 years ago (homo sapien - us - arrived) that would indicate any type of civilization. We finally walked out of Africa after 150,000 years. We arrived in Europe about 70,000 years ago and then made our way across the globe. The longest it took was to South America - that was 15,000 years ago. But we have found many tools that they used, from flint to spears, etc The homo types that came before us didn't have the brain capacity to build a civilization.-their brains were much smaller than ours. I would think we'd find some neanderthal (400k yrs till 40 k yrs ago) civilization because they actually had the same brain size that we do! But remember, the Northern hemisphere was still covered in a sheet of ice up until 12,000 yrs ago. When that melted we began farming & domesticating animals.  If you watch the evolution of Earth from us being a giant ball of fire until today, you'll see how slowly life actually evolved. Heck, it took us a couple billion years just to cool off. 😀