1. Atlantis. I was first introduced to the idea of Thera (now called Santorini, an island near Crete) being Atlantis in a documentary I watched in high school, when all we had was a good guess based on an obvious, devastating volcanic event, a few things we knew from Minoan Crete, and some stone artifacts at the bottom of the Mediterranean. Now we've got more than that: a "Bronze Age Pompeii", as the article calls it, complete with ash-negatives of furniture and rooms left in great haste. There's still no direct link, but the island was a major trading route and someone travelling back to that time would've seen a lot of familiar things—mugs, architectural models, gender equality, multilingualism. (The Therans may have practiced human sacrifice or cannibalism.) Add that to what we know about the volcanic eruption that sank most of the island, and it certain sounds like Atlantis, anyway. A few other things—we've yet to find any bodies, and Thera predated Minoan Crete, if memory serves.*
2. Miami. More specifically, the circular series of holes in a chuck of bedrock, discovered at a proposed building site 10 years ago—with tools, human teeth, and other artifacts. It's probably the foundation of a building, and the Georgian basalt that "contradicts" the leading theory probably isn't a contradiction because there's such a thing as inter-tribal trade, but the fact still remains that the site is c. 2000 years old and as such predates known settlements in the area. There has to be some kind of story in that.
3. India. I know, it seems like a year can't go by without some kind of announcement about humans/humanoids showing up somewhere before they were supposed to, and they're all good story fodder**. This story, "modern humans may have been in India 74,000 years ago, instead of 60,000", is one of many, and I'm using it somewhat as a representative. (I think the Homo florensis stuff is marginally cooler.) Anyway, we get the dates in this instance because the same tools were found under the ash of the Toba super-eruption as were found above it, giving evidence that it was the same culture both times. So, that's about 15,000 years of history we know nothing about. Could this explain the Indus civilization? How vastly does this (or could this) throw off the accepted human colonization routes? What else happened in those 15,000 years that these early humans could've been a part of?
4. Gobekliepe. I started with Atlantis, so feel I should end with something equally cool. You may have heard of Gobekliepe before, since the news broke a few months ago. It's the Turkish Stonehenge, the earliest known place of worship, one that predates*** civilization itself—assuming civilization started in Mesopotamia, which may not exactly be the truth anymore. See, the site means that nomadic people, which these probably were, could organize enough to have religious buildings. That, in turn, means that a "state religion" of sorts, and structures of this scale, don't need to have an agricultural, class-based society in order to exist. One of the theories put forward about this Turkish temple is that the religion and building projects came first, and the agriculture came second, to either make the buildings easier or as a product of people living in a single place over a long period, in order to build the thing. What would that community look like? How does Gobeklipe**** change the way we look at Sumeria, Ur, Babylon, etc? Did civilization get invented in Turkey and then imported to the Fertile Crescent?
I could probably continue with this list, but I suspect it'll be more of the same. Hominids discovered 5000 years before they were supposed to be in Location X. Tools discovered that are more sophisticated than thought. Mysterious buildings and artifacts. Conspiracy theory tie-ins. Any of these stories could provide the foundation for an alternate history, an alien society, or a fantasy world. For starters, we need more Mesopotamian fantasy and more just-the-science Atlantis stories. Go on, you know you want to…
* I'm writing this in transit, so have no net access to check that fact.
** Taking any and all datings with a grain of salt, as they're not always as accurate as some people would like us to believe.
*** There's that word again.
**** I admit it: I just like typing that word.