Paleolithic era

The Paleolithic era is a period of time spanning 2.6 million years ago to 10,000 BCE. This was a point in time when prehistoric man first started wielding stone tools. They were still known for grunting and whacking people across the coconut with wooden clubs, but at least they had the common decency to start wearing furs and skins to cover their junk.

In the very first episode of the original Doctor Who series, "An Unearthly Child", the First Doctor brought Susan Foreman, Barbara Wright and Ian Chesterton back to 100,000 BCE.